> A few overheated transistors may not greatly affect reliability, but the heat generated from a few billion transistors does. This is particularly true for AI/ML/DL designs, where high utilization increases thermal dissipation, but thermal density affects every advanced node chip and package, which are used in smart phones, server chips, AR/VR, and a number of other high-performance devices. For all of them, DRAM placement and performance is now a top design consideration.
I know this may not be a cheap solution, but why not start selling pre-built computers with active cooling systems? Refrigerant liquids like those used in refrigerators or water cooling could be an option. The article addresses this:
> Although it sounds like a near-perfect solution in theory, and has been shown to work in labs, John Parry, industry lead, electronics and semiconductor at Siemens Digital Industries Software, noted that it’s unlikely to work in commercial production. “You’ve got everything from erosion by the fluid to issues with, of course, leaks because you’re dealing with extremely small, very fine physical geometry. And they are pumped. One of the features that we typically find has the lowest reliability associated with it are electromechanical devices like fans and pumps, so you end up with complexity in a number of different directions.”
So instead of integrating fluids within the computer, build powerful mini-freezers for computers and store the computer inside. Or split the warm transistors from the rest of the build and store only those inside the mini freezer, with cables to connect to the rest of the computer outside.
I've seen YouTube videos of overclockers employing refrigeration techniques (or coolants like liquid nitrogen), and it does seem like condensation is a major issue. Maybe that's not as much of a problem at more reasonable temperatures?
But yeah, I'd be just as or more concerned about the amount of power it would take to run a freezer like that ... I'm already drawing as much as 850 watts for my PC, with a max of a couple hundred watts for my OLED TV and speakers, and don't forget the modem and router, and a lamp to top it all off; would a powerful enough mini freezer to cool my PC even fit on the circuit?
Actually, it's even worse because I've got an air purifier running there too ... but I could move that, I suppose.
Cascade cooling is a fun thing. The next step after water cooling before getting to liquid nitrogen...
Still, I wouldn't really go for that. Knowing how noisy the average compressor and fan for that size is. I much prefer my nearly silent fan cooled machine...
Honestly, the fact that my 3080 can draw 400W makes me kind of sick and I limit FPS specifically so it doesn't. I can't ever see myself buying a card that draws double that.
You can reduce the power limit a lot on a 3080 before it impacts performance. The last 3 - 5% of performance they are getting out of their chip is responsible for more than a third of the power draw on higher clocked cards.
Undervolt, friend. I'm running my 3060ti at ~100watts and the overclock is reaching 2150mhz. All while running at around 54 degrees (with a three fan cooler in an air conditioned room)
For most commercial use, you're talking about refrigerated racks. They exist, but they're pretty niche.
In a typical data center, all this does is decentralize your cooling. Now you have many smaller (typically less robust) motors to monitor and replace, and many drain lines much closer to customer equipment and power.
Those units take up a lot more space, too, because of the insulation.
The elevated temperatures of the overheating components are such that fluid flow, not temperature difference, is the thing to go after, and it also has the advantage of being much simpler than adding a whole refrigeration cycle.
These problems start to read like problems from nuclear power, where sufficiently uniform flow is a huge deal so that various materials aren't compromised in the reactor.
why not integrate the ram into the package like apple does anyway and use a slightly larger SoC Cooling solution for the chips? Or just attach headspreaders to ram modules (like gaming modules) and add a fan for them like servers already do due to their general front to back airflow design. The only thing you can't do anymore is relying on the passive cooling of the chips own surface, something CPUs can't do anymore since the early 90s
Big old SoC really do seem like the future. CPU, GPU, RAM, motherboard controllers, throw all those different problem onto a big old die and optimize for cooling that guy.
Yeah I don't understand why a dedicated fan and other basic CPU cooling techniques don't apply here. It's probably because the DRAM industry doesn't want to change form factors and standards to a substantial degree...
... probably because they do the bare minimum to keep up with CPU design and routinely get busted for cartel price fixing and predatory pricing.
That's not going to be viable for servers ror two big reasons:
a) it would big a major capacity limitation; you're not fitting 8-16 DIMMs worth of ram ontop of the CPU. Sure, not everyone fills up their servers, but many do.
b) if you put the ram on top of the cpu, all of the cpu heat needs to transit the ram, which practically means you need a low heat cpu. This works for Apple, their laptop cooling design has never been appropriate for a high heat cpu, but servers manage to cool hundred watt chips in 1U through massive airflow, so high heat enables more computation.
Heatspreaders may make their way into server ram though (although not so big, cause a lot of servers are 1U)
Otoh, the article says
> ‘From zero to 85°C, it operates one way, and at 85° to 90°C, it starts to change,'” noted Bill Gervasi, principal systems architect at Nantero and author of the JEDEC DDR5 NVRAM spec. “From 90° to 95°C, it starts to panic. Above 95°C, you’re going to start losing data, so you’d better start shutting the system down.”
CPUs commonly operate in that temperature range, but RAM doesn't pull that much power, so it doesn't get too much above ambient as long as there's some airflow, and if ambient hits 50C, most people are going to shutdown their severs anyway.
The M1/M2 has the RAM on the same package as the CPU but it's not actually on top of the die, it's adjacent to it. Here's a pic of one someone on reddit delided https://imgur.com/a/RhGk1xw
Obviously this is still a lot of heat in a small space but it does mean the cooler gets to have good coupling with the die rather than going all the way through some DRAM first.
50-100 yrs between major overhaul? When's the last time you had to manually top-up or bleed air out of your circulatory system? I'd say that's impressively robust.
I've always wondered why motherboards aren't placed at a slight angle like the wing of a car so that the air moving over it has a higher angle of incidence, higher pressure, and higher thermal capacity.
With the angle, you can also place cable connectors and whatnot on the bottom of the board so they don't obstruct airflow as much.
Basically, optimize PV = nRT inside the computer case at no extra cost other than a redesign.
I would assume because the things with the greatest heat have typically had such a requirement for active cooling that minor optimization wouldn't have helped much and for everything else you really didn't worry about (though my motherboard now has heat-pipes across the VRMs and my RAM and northbridge have got big old heat spreaders).
Yeah, the way my case is laid out, airflow to the VRM is blocked by the heat spreaders on the RAM and the ATX power connector. AMD systems in particular seem to require better memory thermals.
It seems like we're reaching a point where a new ATX standard is required to ensure the memory and GPU can make contact with a large heatsink similar to how the trashcan Mac Pro and XBox Series X are designed. Doing so would also cut down on the ridiculous number of fans an overclocked gaming PC needs these days, my GPU and CPU heatsinks have 5 80mm fans mounted to them.
ATX is great but it seems like only minor improvements to power connectors and whatnot have been made since it was introduced in 1995.
Are the trashcan Mac Pro and Xbox Series X considered effecient cooling solutions? I thought the trashcan Pro had issues at higher temperatures which in turn limited their ability to use higher end parts and in turn forced the return of the cheese grater?
The series X GPU then is considered equivalent to a desktop 3070, and laptop 3080s exist and are also considered equivalent to a desktop 3070, so don't require anything particularly novel in terms of cooling solutions (3080 laptops are loud under load, but so is the series X).
Overclocked components are so heavy in cooling needs as they're being run so far outside their most efficient window to get the maximum performance - which is why datacenters which care more about energy usage than gamers tend to use lower clocked parts.
Both systems are a fraction of the size of an ATX case and as efficient as they needed to be to meet their predetermined convective cooling needs. In both cases, profit margin is increased by reducing material and shipping volume requirements.
A similar single heatsink design for high end PCs would need to be much larger than either of those designs but considering how much empty space is in an ATX case, I don't think it would be much larger than current PCs.
Or pass liquid through a radiator with comparable volume, standardizing the contact points for a single block heatsink with larger fans would make computers more efficient and quiet.
It won't be a simple redesign to tilt boards "slightly" because manufacturing processes that are already honed in need to be completely retooled, with likely more complexity (man different length of standoffs per board?)
And additionally, there are only a few key components of a motherboard that need cooling. Most of the passive components like the many many decoupling capacitors don't generate significant heat. The components that do require access to cool air are already fitted with finned heat sinks and even additional fans. They interact with air enough to where a slight tilt cannot make a meaningful difference.
Basically just adding a small piece of aluminum to key areas will work better than angling the whole board
I'm struggling slightly to envision the effect you are seeking. My motherboards don't tend to be flying through the air and so lack a well-defined angle of attack... :-) There already exist horizontal and vertical motherboard mounts in different computer cases, including ones that could be stood either way to suit the desktop. In my experience, this doesn't affect cooling that much.
I think the fan, internal baffle, and vent positions dominate the airflow conditions inside the case. So, rather than tilting a motherboard, wouldn't you get whatever you are after with just a slight change in these surrounding structures?
You seem to be ignoring that all the punch through connectors on a board are currently on the side that air must pass over.
Furthermore, I've never seen a case, either desktop or rackmount, that allows one to angle the fans at anything other than a 90 degree angle or parallel to the board.
None of this makes sense in terms of fluid dynamics.
Having a smooth board seems at odds with having a large surface area for heat transfer, doesn't it? And wouldn't laminar flow also have less movement near the surface? For optimal cooling, would you actually want turbulence to mix the layers? Instead of mounting fans at different angles, add some vanes or even duct work to aim and accelerate the flow where it needs to transfer heat.
But, given that boards do not have completely standardized layouts, it seems like you eventually need to assume a forest of independent heat sinks sticking up in the air. You lose the commodity market if everything has to be tailor made, like the integrated heat sink and heat pipe systems in laptops.
You don't really need to pass any air over the PCB, though. Anything that needs cooling sticks up above it. Also the airflow through a case isn't perfectly parallel to the motherboard PCB anyway. GPU fans throw the air in all sorts of directions, including straight down into the motherboard. And so do CPU coolers.
Cables also don't really obstruct the airflow like at all.
Car wings are angled because you're stuck with the direction the wind goes relative to the car (assuming you're driving with all wheels on a surface). Inside a computer, designers have a lot of freedom in where they direct the air flow. So, they plan the layout with space efficiency in mind, taking into account the needs of cooling.
Heat pipes are the phase-change cooling solution that solves all of those issues. People don't really think of their cheap laptop as having a phase-change liquid cooling system, but it actually does.
The article mentions that the automotive industry demands some of the largest temperature ranges for these parts. New cars are basically computers on wheels (especially something like a Tesla), and the cabin in a hot day under a glass roof can easily exceed 170F. Where will the freezer you build around all the computers go, and how will it be powered while the car is sitting parked in a lot?
> I know this may not be a cheap solution, but why not start selling pre-built computers with active cooling systems? Refrigerant liquids like those used in refrigerators or water cooling could be an option.
Before going into water cooling, a change in form factor to allow for better airflow (and mounting of larger heat sinks) would be in order.
Water cooling would require a water cooling block, not sure how it would work with the current form factor.
> So instead of integrating fluids within the computer, build powerful mini-freezers for computers and store the computer inside. Or split the warm transistors from the rest of the build and store only those inside the mini freezer, with cables to connect to the rest of the computer outside.
That's impractical. You are heat exchanging with the air, then you are cooling down the air? Versus exhaust the hot air and bringing more from the outside. You just need to dissipate heat, active cooling is not needed.
Solutions that require increased complexity don't survive in the long run. I remember in the early '70s when my parents bought a new station wagon. This was right when the EPA was cracking down on emissions, and the manufacturers had to jump quick to compensate. Raise the hood on that thing, and you were greeted with a mass of hoses, pipes and components.
Since then, lots and lots of work has gone into making clean engines simpler. Open the hood of a gas-powered car these days and you'll find relative simplicity.
There is a bit of luck in even having any viable materials that work at the required temperature to choose from.
For example, humanity hasn't been able to find a single appropriate material for a superconductor at room temperature/atmospheric pressure despite significant research, but a civilization living below 100 K has a myriad of options to choose from. Superconductors are high technology to us, but if your planet is cold enough then superconducting niobium wire would be a boring household item like copper wire is for us.
Hum... We inhabit that temperature exactly because it allows for a wide range of chemical reactions in a controlled fashion.
The Anthropic Principle is not luck.
We are lucky that those interesting things are possible. We are also unlucky that many interesting things are not possible. But given that they are possible, it was almost inevitable that most of them would be possible around us.
It's also not an absolute. We don't actually know how common life is in environments significantly different from ours, so the part about "wide range of chemical reactions" is just our conjecture.
It’s lucky in the northern hemisphere there is an easily recognizable star pointing almost exactly at the North Pole, which makes navigation much easier.
It’s lucky some available material worked the right way to make a transistor.
It’s lucky some person smart enough to make that work got to work on that.
History is full of lucky coincidences like that. How many Einsteins have died out in the jungle, without access to our scientific knowledge or a way to add to it? For most of history and partly still today, being a scientist wasn’t possible for just about anyone, you had to be from the right family. It’s all about luck.
It's a combination of chemistry and geometry (and other factors). Maybe there's some luck.
There are ICs and components built for operating in extreme environments, like drilling. You can get SiC (silicon carbide) chips that operate above 200°C (473K), if that's important to you. There are also various semiconductors that are worse than silicon at handling high temperatures, like germanium. Old germanium circuits sometimes don't even work correctly on a hot day.
If we lived at 200K, I'm sure that there's a host of semiconductor materials which would be available to us which don't work at 300K.
well, depends how you define lucky. at cryogenic temperature, the leakage current of a transistor is so small that you virtually don't require DRAM refresh. I tested DRAM cells with discharge times of hours, and the transistor was not at all optimized. See https://www.rambus.com/blogs/part-1-dram-goes-cryogenic/ (not my work)
I loved this part at the end:
"By contrast, allowing a temperature increase for chips in large data centers could have surprising environmental benefits. To this point, Keysight’s White recalled that a company once requested JEDEC increase the spec for an operating temperature by five degrees. The estimate of the potential savings was stunning. Based on how much energy they consumed annually for cooling, they calculated a five degree change could translate to shutting down three coal power plants per year. JEDEC ultimately compromised on the suggestion."
Only three? That's not an immediate win. What if the temperature increase causes just so slightly more failures, causing so slightly more replacements, and each replacement requires energy to make, ship, install, replace, recycle, the effects of increased demand... What if it lasts slightly less long, causing more early failures and eWaste? After all that potential risk, is it a benefit still, and if so, how much?
We don't know and it is hard to know - but I don't blame JEDEC and would not call it a "compromise" on their part like it was a superior option.
Cmon.. logically it has to be more than just three right? "Cooling efficiency" sometimes come in unit of W/°C difference, so I'd imagine that a few more degrees would be a huge deal.
I don't know how much power efficiency would be saved - my concern is more that it is completely logical that running any part at higher temperatures causes increased risk of failure, whether it be a computer part or a mechanical part. How much? I don't know - I just don't blame JEDEC for recognizing this is not a clear and obvious win.
Imagine if the failure rate was raised by as little as 1%. RAM Failure is not uncommon compared to other parts - I've had it happen before and render a system unable to boot, that's why we have Memtest86 and not CPUtest86 or SSDtest86. A 1% increase in failure over 5 years would have effects just as unbelievable as the power saving that increasing the temperature would be. How many smartphones would be junked? How many PCs would be thrown out for not working by people who are average Joes who can't diagnose them, and the extra waste that generates from both disposing the old PC and purchasing a new one? Perhaps the new PC is more efficient, but which is better, greater emissions or more eWaste in the ground due to the new PC being likely more efficient than the old one?
The point is that it is not a clear win. With further research it might be, and I might be all for it. I'm only nitpicking the description of it as being a "compromise" as though it were obvious.
[@picture: I'm at my posting limit for the day because HN is, well... I'll leave their censorship policies for another day. I would agree with you if the RAM with the 90C limit were strictly ECC RAM because that is most often used in data centers and not consumer parts. Maybe we have non-ECC/85 RAM and ECC/90 RAM options...]
That's for sure. I 100% agree that increased temperature will statistically increase failure rate. I'm just thinking that, the most common mechanisms of thermal failure in electronics are caused by repeated thermal cycling which cause fatigue and stress failures at interconnects (solder bumps, silicon bonding, etc). Data centers are designed to be operated in a relatively very constant temperature environment, so I would suspect that the failure rate may not be raised significantly.
Well now you're just being hyperbolic. As you say, this is an engineering problem so solutions are far from their ideals states in either direction. However, 1% increase in ram failure rates ruining the world? That doesn't sound right. Errors are encountered in RAM all the time and guess what, they're corrected often by the hardware before even bothering the system. I'm sure we could deal with a 1% increase...
Most datacenter hardware is fine at 95 degrees F (inlet temp). Approved configurations are usually available to 105 degrees F or slightly higher. Some devices can run as high as 130F.
In the operating range, you’re not going to have any measurable change in operations or failure rate - if you do the parts are defective. All of the stories you hear about this and that are conjecture.
Interestingly, computer chips can often be run at lower voltage and wattage for a given frequency if they are kept at a colder temperature. As a home user I can significantly reduce power draw for a CPU/GPU by improving the cooling solution and lowering voltages.
The reasons this doesn't work for datacenters is two-fold, I think: First, they won't see efficiency improvements just by keeping their CPUs and GPUs (or RAM) cooler because the power levels/tables for the chips are baked-in, and operators aren't going to the trouble of tweaking voltages themselves. Second, even if they did tweak voltages, the cost of sustaining lower temperatures with better cooling likely won't outweigh the savings resulting from lower power draw for the chips.
Still, this raises the question of whether designing hardware for higher operating temperatures is always the right move. At some point there's going to be a cost in performance and/or efficiency that outweighs the savings from allowing higher temperatures. Ideally these tradeoffs should be balanced as a whole.
I think you missed the biggest reason this doesn't do much for servers - they already run at low frequencies & voltages.
For example take the Epyc 7742, at 225W it sounds super power hungry. But the 64-core chip only boosts to 3.4ghz max (2.25ghz base). That's less than the base clock of almost any of the Ryzen consumer CPUs. And if you look at the lower frequency end of https://images.anandtech.com/doci/16214/PerCore-1-5950X.png there's not a whole heck of a lot of efficiency gains likely to be had below that ~3-3.4ghz mark. They're already basically sipping power at something like 3w per CPU core or less. 225w / 64c = 3.5w/c, but the IO uncore isn't exactly cheap to run and iirc sits more like in the 50-70w range. So subtract that out and you're at more like 2.5-2.7w/c. I don't think throwing cooling at this is really going to get you much of a gain.
This usually isn't true at scale though. The chip manufacturers do a ton of validation and qualification to set the operating parameters (voltage, etc).
You can undervolt (or overclock) one specific chip, individuals have been doing this at home for basically ever, but there's (almost) always a system-specific validation process you then do to make sure the system is stable for a specific workload with the new parameters.
And these parameters differ between batches of chips, or even between chips within a batch.
It's also significantly harder to drastically reduce the temperature of the chips inside of a single server, given the machine density of a typical data center.
> It's also significantly harder to drastically reduce the temperature of the chips inside of a single server, given the machine density of a typical data center.
It’d be fun, however, if we could dynamically adjust that according to workload. If workload is light, you could consolidate load into fewer sockets/memory sticks and power down everything in that socket.
It’s been a while since I was doing hardware in a DC, but even dynamic frequency changes in servers were noticeable in workloads.
We’d see serious latency spikes with high volume increases. And high volume would correlate to high I/O on shared storage exacerbating the problem.
You’d get a bunch of transactional failures from the spontaneous latency hit.
Same was true with older virtualization/partitioning of hardware. You’d even see apps back up into memory and swap themselves to death.
Now, the apps were awful: inefficient and intolerant. But that’s the reality for the vast majority of business software. Churned out by devs with little understanding and tight timelines for features.
You usually have to budget a few °C of difference just for pushing enough energy through heat exchangers. So the rate of chip temperature / external temperature is lower than the rate that effectively determines the cooling efficiency.
When I was on an architecture team that consolidated ~80 datacenter to 3 circa 2010, this was a key dollar driver. We raised the temperature ~6 degrees from the average temp, which meant kicking out a few vendors initially. The cost savings for doing that was essentially the total operational costs of 5 datacenters.
The annual failure rates for the hardware did not change at all by any metric. Number of service impacting hardware failures went to zero due to the consolidation.
In general, if you operate within the operating ranges of your hardware, you won’t have failure. You will have complaints from employees, because computers will operate at temperatures not comfortable for humans.
We did the same several years ago.
At the time I found http://www.cs.toronto.edu/~bianca/papers/temperature_cam.pdf quite interesting.
I didn't find many other precise papers about issues when running at a higher temperatures, but many "should" and "can".
We found (by measurement) that some places in the datacenter with suboptimal airflow are well over the average or simulated temperature so one can leave the safe temperature envelope if one isn't careful.
It's almost certainly Google, since they've historically ran their data centers hotter than most [0]. Cooling efficiency increases with a higher delta-T to the working fluid, and Google uses a gigawatt or two continuously [1]. From PUE numbers that's hundreds of MW spent on cooling, so making it more efficient is quite worth it.
I’m not in this game anymore, but I remember Yahoo built a datacenter in NY off Lake Erie that wasn’t cooled. They aligned the building lengthwise on a ridge above the lake and just blew air through it with no AC. No idea how it operated though.
> The annual failure rates for the hardware did not change at all by any metric.
I don't know what kind of magical hardware you ran, but from the datacenters I've interacted with this is absolute nonsense. Higher temps and/or humidity have an immediate effect on failure rates, to the point where we could plan extra time for them next week if the temp raised even .5 degrees.
Well, sometimes, and more frequently now at really small process nodes, but mostly no. Most electronic failures are basically mechanical and thermal cycling will cause fatigue failures more than elevated temperatures will accelerate things like electromigration. Lots of people still use 1960s style handbook methods anyway because there's no plug-and-chug replacement.
Could also be more likely that it's cheaper to extend the life of an older DC by accepting higher temperatures and failure rates than to upgrade the hvac to accommodate newer higher density designs
Depending on design, if the DC isn't very monolithic, then you can run with components failing and not causing much trouble, replacing when available, if your apps are designed to run on a zillion small CPUs, as I believe Google and Amazon are, instead of a giant monolithic computer, 1970s style.
Could have heavier AC for critical components, the main routers and disk farms, for instance.
Maybe RAM will finally get more than a 4mm thermal pad and a random bit of Alu for cooling. Seems like most cooling designs have treated RAM as even more of an after thought than VRMs up until recently.
Even in most servers the accommodation for RAM cooling has basically just been orientating the DIMMs to line up with airflow. They are still packed together with minimal clearance.
I am not sure how much this is related to external cooling versus actually internal thermal dissipation. DDR JEDEC standards have actually decreased power consumption on every generation.
They have reduced voltage but power consumption per sq-mm has gone up with increased densities. Many people run DRAM at above JEDEC speeds which usually requires higher voltages too.
Peak power consumption of DDR4 is around 375mW/GB @ 1.2V, DDR5 drops this about 10% but also increases the maximum density of a DIMM by 8x to 512GB which is like, 150W for a single DIMM.
There are only three (tiny) 12 V power pins on a DDR5 module, neither that nor the form factor allows for dissipating anywhere close to 150 W. The teased 512 GB Samsung module doesn't even have a heatspreader.
If I had to guess, Servers would not go any further than some sort of memory-backplane where the memory for multiple channels was integrated onto a single PCB.
Even then, IIRC hot-swapping of memory modules is a thing for some servers, so that will have to be handled somehow.
You still need to conduct the heat away from the sources to a radiator of some sort, since cooling is proportional to surface area and it’s much easier to increase surface area by adding fins than by increasing airflow. You can only speed up the air to a certain point, past which better cooling becomes a matter of shaping the components for more contact with the air.
Yeah, kinda weird that on ATX RAM is placed in way that is perpendicular to usual CPU cooling or even general air flow. The top mounted fans do change this, but I don't think those are very common.
This design would have made so much more sense before the top of the case closed loop watercooler radiator setups became popular.
I still like this a lot, but now the top down fan and some kind of ducting to help direct the air out the top / side vent makes more sense. There's so much heat these days everyone needs the baffles inside of a case.
That kingpin design is really for extreme overclocking and is about ensuring best possible signal integrity. Hence why it also only has 2 ram slots. But it demonstrates what's possible. In reality the RAM barely needs any cooling anyway and if you really care you can get one of those clip on fan brackets like this https://www.corsair.com/us/en/Categories/Products/Accessorie...
I'm not in the field, but I have seen some of the work done by thermal engineers designing new server systems, and no that's not the case.
Cost, noise, and physical box size are to be minimized, and various compute/storoage/io capacity are to be maximized. Component placement and orientation relative to one another, baffles, fan characteristics heat sink design, all play a role.
They don't just throw parts in a box and add fans until all components are within operating temperature. Gross air flow is one lever, but it has costs and limits like all the others. Designs are modeled with heat and fluid simulations.
What thermal issues? All I've seen so far are people who don't seem to understand how passive cooling works, despite the M1 Air being out for two years and working the same way.
A laptop with two fans that gets too hot to comfortably touch, even under light workloads, unless you set it to throttle all the time? That's a heat problem.
The M2 chip generates more heat than the M1, with 20% more transistors and about a 12% higher clock speed. M2 Mac Pro has thermal issues compared to M1 Mac Pro as well, even with the fan.
I think it's just expectations, people expected a brand new laptop should be able to perform fully without throttling. And that the throttling is designed as a crutch to prevent hardware damage.
One can draw different thresholds, ie. 100% performance for x amount of time before throttling happens etc..
That’s the key I’ve heard. Yes the M2 throttles in the Air (where the M1 would sometimes) and the 13” (where the M1 was fine).
But the M2, throttling included, was still 10-20% faster than the M1 when it never throttled. Sorry but I don’t remember the exact numbers.
So basically it’s sort of a non-issue. You were promised a faster laptop and you got one. Yes it’s not up to it’s theoretical potential but it’s not like it’s at 100% or less what the M1 did.
The 13” is kind of a weird computer anyway. The 14” and 16” will be a much bigger test. We’ll see how that fairs.
There are very few thin and light laptops that can reach thermal equilibrium with their CPUs boosting and under 100 % load. The M2 Air is no different from the M1 Air or any other competitor, it even throttles LESS than the M1 Air.
This whole thing just doesn't make sense, according to the youtubers the M1 Air was half computer and half the Second Coming of Christ (and it's a lovely machine, I have one), and then the next generation comes, IMPROVES both the performance and the thermal behavior, and suddenly there's an issue.
May also depend on the efficacy of the throttle. A crude throttle that cuts TDP 20% but cuts performance 50% is a bad user experience.
It could be interesting in the future to talk about platform-constrained performance. In other words, take two 28W chips in 15W platforms. Both can boost for short periods. But how do each perform when throttled to 15W?
Still waiting to see the first micro-engineered Stirling engine that
can self-cool. Any physicists care to comment on why that won't work
yet, or ever?
You can only cool something by making something else warmer by a larger amount. The heat has to go somewhere, and moving that heat in any non-passive way will invariably produce yet more heat in the process.
> You can only cool something by making something else warmer by a larger amount.
Why isn't it also true that you can only make something warmer, by cooling something else by a larger amount?
The movement of electricity generates waste heat, why isn't that process reversible? Making the heat disappear into a cold wire, rather than just dissipating into the atmosphere? (not suggesting it's would be easy or even practical).
2nd law of thermodynamics - entropy is always increasing. Heat transfer is never 100% efficient, you always lose something in transmission. This is also why it's not possible to create a perpetual-motion machine.
Peltier coolers [1] do exist for specialist applications but they are
not at all effective. You can even buy them on Amazon. If the goal is
to iron out a spike to stop your semiconductor from going into thermal
runaway (instead of generating net energy as is the knee-jerk of some
unimaginative down-voters here) then it's a possible saviour.
I think some people are interpreting that as a joke. I'm not talking
about a net gain of energy or any crazy perpetual motion machine.
Think of something like a "heat brake". Differential heat energy can
be converted to mechanical work. Some of that can be used to cool the
system elsewhere, creating a negative feedback loop. Another way to
think of such a system is like the "reluctance" of an inductor.
With present thermoelectric effects, using a Seebeck junction to
generate current for a fan is hopelessly ineffective. But is that
necessarily the case for all designs which could help to hold a system
under a critical temperature when heat spikes.
That's an example of a similar system, but probably impractical for
use in an electronics context. I have in my imagination a fantasy
"smart" material that in the limit can transfer 0.5 * k^m joules of
heat per square meter per second from one side to the other (where m
is somewhere between 1 and 2). Such a material would always feel
slightly warmer on one side and cooler on the other, and this effect
would actually increase in the presence of ambient heat, hence it
could act as a thermal "brake" or active heat pipe/diode. I beleieve
such a device is "allowable" within the laws of physics.
The goal is to quickly and efficiently conduct heat from the DRAM (A) to the outside world (B). You could generate a little power from the temperature difference between A and B, but that would greatly reduce the effectiveness of the heat transfer. Perhaps that generated power could cool something else, but you'd waste power (and generate heat) in the process. Net loss.
IIRC TSMC's 135MBit 5nm example is 79.8mm^2, although that's got other logic.
In the abstract, a 0.021 square-micrometer-per-bit size [1] says you'd need about 21mm^2 for a gigabit (base 10) of 5nm SRAM, without other logic.
Micron claimed 0.315Gb/mm^2 on their 14nm process, [2] so somewhere between a factor of 6 and 7.
That said, my understanding is that there is some sort of wall around 10nm, where we can't really make smaller capacitors and thus the limitation on things. (This may have changed since I last was aware however.)
(There is also the way than 'nm' works these days... but I'm not qualified to speak on that)
Also, AFAIK SRAM is still broadly speaking more power hungry than DRAM (I may be completely out of date on this though...)
RAM has been parallel for ages. IBM's new POWER10 achitecture switches to serial control of ram with firmware running on the ram sticks. As long as complex mitigations and monitoring are going to be required this might be the way to go.
Next, we'll have a generation of mobile devices that will be liquid cooled. Of course because of the miniturization, there will be no way to refill the liquid coolant without getting a new device. This will naturally happen before the batteries die creating an even shorter life cycle in devices. Sounds like a perfect pitch for an upcoming WWDC type of event.
A lot more refresh commands are issued. A single cell holds data for 64 milliseconds. But a refresh only refreshes a subset of the RAM, a full row. So to refresh an entire chip you need to refresh all rows which can be hundreds to thousands of rows. So in practice you need to issue refreshes every few microseconds to ensure you hit every cell at least once every 64ms.
Does DRAM really get that hot now? I remember the huge amount of products aimed at cooling DIMMs appeared around 15-20 years ago and largely dismissed them as unnecessary "bling", and closer to a decade ago, on a regular desktop PC, had some that came with heatspreaders; nonetheless, after a weekend-long Linpack run to ensure stability of an overclock, during which the CPU was constantly well above ambient at around 70C, reached in and cautiously felt the heatspreaders on the DIMMs --- and was surprised to discover that they were only slightly warm, probably around 40C.
"And it’s not just servers. With about 8 billion transistors on a single die, a mobile phone can get so hot it might need to spend a few minutes in a refrigerator. When that happens, the apps will fail to function correctly."
Such a weird way to phrase this! All I can think is ".. and it's hard to use your phone when it's in the fridge"?
I have one of those magnetic phone holders that attach to the aircon vents in your car. Every time I use it with the air con on in the summer I think about how my phone could probably use the extra cooling for a performance boost, except it's not really needed just for running google maps.
And then when I do the same thing in the winter I have to be careful about turning the heater on because the hot air will make my phone auto shut down from the heat.
They could do a lot by just putting 1.5mm height aluminum fin heatsinks on DIMMs as compared to the extremely cheap flat heat spreaders commonly used now.
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[ 3.9 ms ] story [ 234 ms ] threadI know this may not be a cheap solution, but why not start selling pre-built computers with active cooling systems? Refrigerant liquids like those used in refrigerators or water cooling could be an option. The article addresses this:
> Although it sounds like a near-perfect solution in theory, and has been shown to work in labs, John Parry, industry lead, electronics and semiconductor at Siemens Digital Industries Software, noted that it’s unlikely to work in commercial production. “You’ve got everything from erosion by the fluid to issues with, of course, leaks because you’re dealing with extremely small, very fine physical geometry. And they are pumped. One of the features that we typically find has the lowest reliability associated with it are electromechanical devices like fans and pumps, so you end up with complexity in a number of different directions.”
So instead of integrating fluids within the computer, build powerful mini-freezers for computers and store the computer inside. Or split the warm transistors from the rest of the build and store only those inside the mini freezer, with cables to connect to the rest of the computer outside.
But yeah, I'd be just as or more concerned about the amount of power it would take to run a freezer like that ... I'm already drawing as much as 850 watts for my PC, with a max of a couple hundred watts for my OLED TV and speakers, and don't forget the modem and router, and a lamp to top it all off; would a powerful enough mini freezer to cool my PC even fit on the circuit?
Actually, it's even worse because I've got an air purifier running there too ... but I could move that, I suppose.
Still, I wouldn't really go for that. Knowing how noisy the average compressor and fan for that size is. I much prefer my nearly silent fan cooled machine...
In a typical data center, all this does is decentralize your cooling. Now you have many smaller (typically less robust) motors to monitor and replace, and many drain lines much closer to customer equipment and power.
Those units take up a lot more space, too, because of the insulation.
These problems start to read like problems from nuclear power, where sufficiently uniform flow is a huge deal so that various materials aren't compromised in the reactor.
In theory you can eliminate condensation.
But in practice, there's a difference between theory and practice.
I am sure there is a lot more to it than that though... ha
... probably because they do the bare minimum to keep up with CPU design and routinely get busted for cartel price fixing and predatory pricing.
That's not going to be viable for servers ror two big reasons:
a) it would big a major capacity limitation; you're not fitting 8-16 DIMMs worth of ram ontop of the CPU. Sure, not everyone fills up their servers, but many do.
b) if you put the ram on top of the cpu, all of the cpu heat needs to transit the ram, which practically means you need a low heat cpu. This works for Apple, their laptop cooling design has never been appropriate for a high heat cpu, but servers manage to cool hundred watt chips in 1U through massive airflow, so high heat enables more computation.
Heatspreaders may make their way into server ram though (although not so big, cause a lot of servers are 1U)
Otoh, the article says
> ‘From zero to 85°C, it operates one way, and at 85° to 90°C, it starts to change,'” noted Bill Gervasi, principal systems architect at Nantero and author of the JEDEC DDR5 NVRAM spec. “From 90° to 95°C, it starts to panic. Above 95°C, you’re going to start losing data, so you’d better start shutting the system down.”
CPUs commonly operate in that temperature range, but RAM doesn't pull that much power, so it doesn't get too much above ambient as long as there's some airflow, and if ambient hits 50C, most people are going to shutdown their severs anyway.
Maybe instead of 32 RAM packages and 4 CPU packages, we could have 16 CPU packages each with onboard RAM?
Obviously this is still a lot of heat in a small space but it does mean the cooler gets to have good coupling with the die rather than going all the way through some DRAM first.
However there are ways to prevent and detect leaks in current system with negative pressure: https://www.youtube.com/watch?v=UiPec2epHfc
With the angle, you can also place cable connectors and whatnot on the bottom of the board so they don't obstruct airflow as much.
Basically, optimize PV = nRT inside the computer case at no extra cost other than a redesign.
It seems like we're reaching a point where a new ATX standard is required to ensure the memory and GPU can make contact with a large heatsink similar to how the trashcan Mac Pro and XBox Series X are designed. Doing so would also cut down on the ridiculous number of fans an overclocked gaming PC needs these days, my GPU and CPU heatsinks have 5 80mm fans mounted to them.
ATX is great but it seems like only minor improvements to power connectors and whatnot have been made since it was introduced in 1995.
The series X GPU then is considered equivalent to a desktop 3070, and laptop 3080s exist and are also considered equivalent to a desktop 3070, so don't require anything particularly novel in terms of cooling solutions (3080 laptops are loud under load, but so is the series X).
Overclocked components are so heavy in cooling needs as they're being run so far outside their most efficient window to get the maximum performance - which is why datacenters which care more about energy usage than gamers tend to use lower clocked parts.
A similar single heatsink design for high end PCs would need to be much larger than either of those designs but considering how much empty space is in an ATX case, I don't think it would be much larger than current PCs.
Consider that the best PC cooling solutions all look like this: https://assets1.ignimgs.com/2018/01/18/cpucooler-1280-149617...
Or pass liquid through a radiator with comparable volume, standardizing the contact points for a single block heatsink with larger fans would make computers more efficient and quiet.
And additionally, there are only a few key components of a motherboard that need cooling. Most of the passive components like the many many decoupling capacitors don't generate significant heat. The components that do require access to cool air are already fitted with finned heat sinks and even additional fans. They interact with air enough to where a slight tilt cannot make a meaningful difference.
Basically just adding a small piece of aluminum to key areas will work better than angling the whole board
I think the fan, internal baffle, and vent positions dominate the airflow conditions inside the case. So, rather than tilting a motherboard, wouldn't you get whatever you are after with just a slight change in these surrounding structures?
Furthermore, I've never seen a case, either desktop or rackmount, that allows one to angle the fans at anything other than a 90 degree angle or parallel to the board.
None of this makes sense in terms of fluid dynamics.
But, given that boards do not have completely standardized layouts, it seems like you eventually need to assume a forest of independent heat sinks sticking up in the air. You lose the commodity market if everything has to be tailor made, like the integrated heat sink and heat pipe systems in laptops.
Cables also don't really obstruct the airflow like at all.
Before going into water cooling, a change in form factor to allow for better airflow (and mounting of larger heat sinks) would be in order.
Water cooling would require a water cooling block, not sure how it would work with the current form factor.
> So instead of integrating fluids within the computer, build powerful mini-freezers for computers and store the computer inside. Or split the warm transistors from the rest of the build and store only those inside the mini freezer, with cables to connect to the rest of the computer outside.
That's impractical. You are heat exchanging with the air, then you are cooling down the air? Versus exhaust the hot air and bringing more from the outside. You just need to dissipate heat, active cooling is not needed.
Since then, lots and lots of work has gone into making clean engines simpler. Open the hood of a gas-powered car these days and you'll find relative simplicity.
For example, humanity hasn't been able to find a single appropriate material for a superconductor at room temperature/atmospheric pressure despite significant research, but a civilization living below 100 K has a myriad of options to choose from. Superconductors are high technology to us, but if your planet is cold enough then superconducting niobium wire would be a boring household item like copper wire is for us.
The Anthropic Principle is not luck.
We are lucky that those interesting things are possible. We are also unlucky that many interesting things are not possible. But given that they are possible, it was almost inevitable that most of them would be possible around us.
It’s lucky some available material worked the right way to make a transistor.
It’s lucky some person smart enough to make that work got to work on that.
History is full of lucky coincidences like that. How many Einsteins have died out in the jungle, without access to our scientific knowledge or a way to add to it? For most of history and partly still today, being a scientist wasn’t possible for just about anyone, you had to be from the right family. It’s all about luck.
There are ICs and components built for operating in extreme environments, like drilling. You can get SiC (silicon carbide) chips that operate above 200°C (473K), if that's important to you. There are also various semiconductors that are worse than silicon at handling high temperatures, like germanium. Old germanium circuits sometimes don't even work correctly on a hot day.
If we lived at 200K, I'm sure that there's a host of semiconductor materials which would be available to us which don't work at 300K.
We don't know and it is hard to know - but I don't blame JEDEC and would not call it a "compromise" on their part like it was a superior option.
Imagine if the failure rate was raised by as little as 1%. RAM Failure is not uncommon compared to other parts - I've had it happen before and render a system unable to boot, that's why we have Memtest86 and not CPUtest86 or SSDtest86. A 1% increase in failure over 5 years would have effects just as unbelievable as the power saving that increasing the temperature would be. How many smartphones would be junked? How many PCs would be thrown out for not working by people who are average Joes who can't diagnose them, and the extra waste that generates from both disposing the old PC and purchasing a new one? Perhaps the new PC is more efficient, but which is better, greater emissions or more eWaste in the ground due to the new PC being likely more efficient than the old one?
The point is that it is not a clear win. With further research it might be, and I might be all for it. I'm only nitpicking the description of it as being a "compromise" as though it were obvious.
[@picture: I'm at my posting limit for the day because HN is, well... I'll leave their censorship policies for another day. I would agree with you if the RAM with the 90C limit were strictly ECC RAM because that is most often used in data centers and not consumer parts. Maybe we have non-ECC/85 RAM and ECC/90 RAM options...]
In the operating range, you’re not going to have any measurable change in operations or failure rate - if you do the parts are defective. All of the stories you hear about this and that are conjecture.
The reasons this doesn't work for datacenters is two-fold, I think: First, they won't see efficiency improvements just by keeping their CPUs and GPUs (or RAM) cooler because the power levels/tables for the chips are baked-in, and operators aren't going to the trouble of tweaking voltages themselves. Second, even if they did tweak voltages, the cost of sustaining lower temperatures with better cooling likely won't outweigh the savings resulting from lower power draw for the chips.
Still, this raises the question of whether designing hardware for higher operating temperatures is always the right move. At some point there's going to be a cost in performance and/or efficiency that outweighs the savings from allowing higher temperatures. Ideally these tradeoffs should be balanced as a whole.
For example take the Epyc 7742, at 225W it sounds super power hungry. But the 64-core chip only boosts to 3.4ghz max (2.25ghz base). That's less than the base clock of almost any of the Ryzen consumer CPUs. And if you look at the lower frequency end of https://images.anandtech.com/doci/16214/PerCore-1-5950X.png there's not a whole heck of a lot of efficiency gains likely to be had below that ~3-3.4ghz mark. They're already basically sipping power at something like 3w per CPU core or less. 225w / 64c = 3.5w/c, but the IO uncore isn't exactly cheap to run and iirc sits more like in the 50-70w range. So subtract that out and you're at more like 2.5-2.7w/c. I don't think throwing cooling at this is really going to get you much of a gain.
You can undervolt (or overclock) one specific chip, individuals have been doing this at home for basically ever, but there's (almost) always a system-specific validation process you then do to make sure the system is stable for a specific workload with the new parameters.
And these parameters differ between batches of chips, or even between chips within a batch.
It's also significantly harder to drastically reduce the temperature of the chips inside of a single server, given the machine density of a typical data center.
It’d be fun, however, if we could dynamically adjust that according to workload. If workload is light, you could consolidate load into fewer sockets/memory sticks and power down everything in that socket.
We’d see serious latency spikes with high volume increases. And high volume would correlate to high I/O on shared storage exacerbating the problem. You’d get a bunch of transactional failures from the spontaneous latency hit.
Same was true with older virtualization/partitioning of hardware. You’d even see apps back up into memory and swap themselves to death.
Now, the apps were awful: inefficient and intolerant. But that’s the reality for the vast majority of business software. Churned out by devs with little understanding and tight timelines for features.
Reliability being an NFR kills me.
When I was on an architecture team that consolidated ~80 datacenter to 3 circa 2010, this was a key dollar driver. We raised the temperature ~6 degrees from the average temp, which meant kicking out a few vendors initially. The cost savings for doing that was essentially the total operational costs of 5 datacenters.
The annual failure rates for the hardware did not change at all by any metric. Number of service impacting hardware failures went to zero due to the consolidation.
In general, if you operate within the operating ranges of your hardware, you won’t have failure. You will have complaints from employees, because computers will operate at temperatures not comfortable for humans.
Based on ASHARE there are two guidelines from HPE and IBM: https://www.chiltrix.com/documents/HP-ASHRAE.pdf https://www.ibm.com/downloads/cas/1Q94RPGE
We found (by measurement) that some places in the datacenter with suboptimal airflow are well over the average or simulated temperature so one can leave the safe temperature envelope if one isn't careful.
The hyper scale people take this to the next degree.
[0] https://www.google.com/about/datacenters/efficiency/ [1] https://www.cnbc.com/2022/04/13/google-data-center-goal-100p...
edit: this makes me wonder what is the ideal humidity in a data centre? Is too dry a thing?
I’m not in this game anymore, but I remember Yahoo built a datacenter in NY off Lake Erie that wasn’t cooled. They aligned the building lengthwise on a ridge above the lake and just blew air through it with no AC. No idea how it operated though.
I don't know what kind of magical hardware you ran, but from the datacenters I've interacted with this is absolute nonsense. Higher temps and/or humidity have an immediate effect on failure rates, to the point where we could plan extra time for them next week if the temp raised even .5 degrees.
Cheaper to have a slightly higher failure rate, or have the computers throttle their clock speed, than to pay for extra air conditioning.
Of course you'll need some data for calibrating the model, but if you got that?
[1]: https://en.wikipedia.org/wiki/Arrhenius_equation
[2]: https://www.ti.com/lit/an/snva509a/snva509a.pdf
The groundbreaking work here was by Michael Pecht back in the early nineties: https://apps.dtic.mil/sti/pdfs/ADA275029.pdf
Downtime isn't free.
Depending on design, if the DC isn't very monolithic, then you can run with components failing and not causing much trouble, replacing when available, if your apps are designed to run on a zillion small CPUs, as I believe Google and Amazon are, instead of a giant monolithic computer, 1970s style.
Could have heavier AC for critical components, the main routers and disk farms, for instance.
Details of the calculations unknown to me.
Even in most servers the accommodation for RAM cooling has basically just been orientating the DIMMs to line up with airflow. They are still packed together with minimal clearance.
Peak power consumption of DDR4 is around 375mW/GB @ 1.2V, DDR5 drops this about 10% but also increases the maximum density of a DIMM by 8x to 512GB which is like, 150W for a single DIMM.
https://media-www.micron.com/-/media/client/global/documents...
Looking a bit closer I think you are right that it's 12V but only for Registered DIMMs.
If I had to guess, Servers would not go any further than some sort of memory-backplane where the memory for multiple channels was integrated onto a single PCB.
Even then, IIRC hot-swapping of memory modules is a thing for some servers, so that will have to be handled somehow.
Isn't that server cooling in a nutshell? Ram high volumes of airflow through the chassis with stupidly loud fans and hope the parts stay cool?
I still like this a lot, but now the top down fan and some kind of ducting to help direct the air out the top / side vent makes more sense. There's so much heat these days everyone needs the baffles inside of a case.
Cost, noise, and physical box size are to be minimized, and various compute/storoage/io capacity are to be maximized. Component placement and orientation relative to one another, baffles, fan characteristics heat sink design, all play a role.
They don't just throw parts in a box and add fans until all components are within operating temperature. Gross air flow is one lever, but it has costs and limits like all the others. Designs are modeled with heat and fluid simulations.
This review of Lenovo's new Thinkpad X1 Yoga is what a heat problem looks like:
>Unfortunately, the laptop got uncomfortably hot in its Best performance mode during testing, even with light workloads.
https://arstechnica.com/gadgets/2022/07/review-lenovos-think...
A laptop with two fans that gets too hot to comfortably touch, even under light workloads, unless you set it to throttle all the time? That's a heat problem.
One can draw different thresholds, ie. 100% performance for x amount of time before throttling happens etc..
But the M2, throttling included, was still 10-20% faster than the M1 when it never throttled. Sorry but I don’t remember the exact numbers.
So basically it’s sort of a non-issue. You were promised a faster laptop and you got one. Yes it’s not up to it’s theoretical potential but it’s not like it’s at 100% or less what the M1 did.
The 13” is kind of a weird computer anyway. The 14” and 16” will be a much bigger test. We’ll see how that fairs.
This whole thing just doesn't make sense, according to the youtubers the M1 Air was half computer and half the Second Coming of Christ (and it's a lovely machine, I have one), and then the next generation comes, IMPROVES both the performance and the thermal behavior, and suddenly there's an issue.
It could be interesting in the future to talk about platform-constrained performance. In other words, take two 28W chips in 15W platforms. Both can boost for short periods. But how do each perform when throttled to 15W?
Why isn't it also true that you can only make something warmer, by cooling something else by a larger amount?
The movement of electricity generates waste heat, why isn't that process reversible? Making the heat disappear into a cold wire, rather than just dissipating into the atmosphere? (not suggesting it's would be easy or even practical).
https://en.wikipedia.org/wiki/Second_law_of_thermodynamics
[1] https://www.britannica.com/science/Seebeck-effect
[2] https://www.amazon.com/Peltier-Cooler/s?k=Peltier+Cooler
With present thermoelectric effects, using a Seebeck junction to generate current for a fan is hopelessly ineffective. But is that necessarily the case for all designs which could help to hold a system under a critical temperature when heat spikes.
https://en.wikipedia.org/wiki/Solar_chimney
IIRC TSMC's 135MBit 5nm example is 79.8mm^2, although that's got other logic.
In the abstract, a 0.021 square-micrometer-per-bit size [1] says you'd need about 21mm^2 for a gigabit (base 10) of 5nm SRAM, without other logic.
Micron claimed 0.315Gb/mm^2 on their 14nm process, [2] so somewhere between a factor of 6 and 7.
That said, my understanding is that there is some sort of wall around 10nm, where we can't really make smaller capacitors and thus the limitation on things. (This may have changed since I last was aware however.)
(There is also the way than 'nm' works these days... but I'm not qualified to speak on that)
Also, AFAIK SRAM is still broadly speaking more power hungry than DRAM (I may be completely out of date on this though...)
[1] - https://fuse.wikichip.org/news/3398/tsmc-details-5-nm/
[2] - https://semiengineering.com/micron-d1%CE%B1-the-most-advance...
> (as a standard metric, about once every 64 milliseconds)
64 milliseconds? wow.. I thought they'd need refreshing way more often
"And it’s not just servers. With about 8 billion transistors on a single die, a mobile phone can get so hot it might need to spend a few minutes in a refrigerator. When that happens, the apps will fail to function correctly."
Such a weird way to phrase this! All I can think is ".. and it's hard to use your phone when it's in the fridge"?
And then when I do the same thing in the winter I have to be careful about turning the heater on because the hot air will make my phone auto shut down from the heat.