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Any EEs that can comment on at what point do we just flip the architecture over so the GPU pcb is the motherboard and the cpu/memory lives on a PCIe slot? It seems like that would also have some power delivery advantages.
If you look at a any of the nvidia DGX boards it's already pretty close.

PCIe is a standard/commodity so that multiple vendors can compete and customers can save money. But at 8.0 speeds I'm not sure how many vendors will really be supplying, there's already only a few doing serdes this fast...

Yes I agree, let's bring back the SECC style CPU's from the Pentium Era, I've still got my Pentium II (with MMX technology)
Isn't that what has kinda sorta basically happened with Apple Silicon?
And limit yourself to only one GPU?

Also CPUs are able to make use of more space for memory, both horizontally and vertically.

I don't really see the power delivery advantages, either way you're running a bunch of EPS12V or similar cables around.

Figure out how much RAM, L1-3|4 cache, integer, vector, graphics, and AI horsepower is needed for a use-case ahead-of-time and cram them all into one huge socket with intensive power rails and cooling. The internal RAM bus doesn't have to be DDRn/X either. An integrated northbridge would deliver PCIe, etc.
> at what point do we just flip the architecture over so the GPU pcb is the motherboard and the cpu/memory

Actually the RapsberryPi (appeared 2012) was based on a SoC with a big and powerful GPU and small weak supporting CPU. The board booted the GPU first.

Bring back the S100 bus and put literally everything on a card. Your motherboard is just a dumb bus backplane.
One possible advantage of this approach that no one here has mentioned yet is that it would allow us to put RAM on the CPU die (allowing for us to take advantage of the greater memory bandwidth) while also allowing for upgradable RAM.
Can I just have a backplane? Pretty please?
Wouldn't that mean an complete mobo replacement to upgrade the GPU? GPU upgrades seem much more rapid and substantial compared to CPU/RAM. Each upgrade would now mean taking out the CPU/RAM and other cards vs just replacing the GPU
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The concept exists now. You can "reverse offload" work to the CPU.
EE here. There's no reason to not deliver power directly to the GPU by using cables. I'm not sure if it's sooving anything.

But you are right, there's no hierarchy in the systems anymore. Why do we even call something a motherboard? There's a bunch of chips interconnected.

It is not a EE problem. It is an ecosystem problem. You need a whole catalog of compatible hardware for this.
I wonder how many additional layers are required in the PCB to achieve this + how this will dramatically affect the TDP; the GPU's aren't the only components with heat tolerance and capacitance.
Personally I hope this point comes after we realise we don't need 1kW GPUs doing a whole lot of not much useful
My reaction to PCIe gen 8 is essentially "Huh? No, retro data buses are like ISA, PCI, and AGP, right? PCIe Gen 3 and SATA are still pretty new...".

I wonder what modulation order / RF bandwidth they'll be using on the PHY for Gen8. I think Gen7 used 32GHz, which is ridiculously high.

I love the PCIe standard is 3 generations ahead of what is actually released. Gen5 is the live version, but the team behind it is so well organized that they have a roadmap of 3 additional versions now. Love it.
I'll take it if my consumer mb chipset supports giving me 48 PCIe7 lanes if future desktops still would only come with 24 gen 8 lanes
Meanwhile paying a premium for a Gen5 motherboard may net you somewhere in the realm of 4% improvements in gaming if you're lucky.

Obviously PCI is not just about gaming but...

I thought we were only just up to 5? Did we skip 6 and 7?
I know very little about electronics design, so I always find it amazing that they keep managing to double PCIe throughput over and over. Its also probably the longest lived expansion bus at the moment.
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Yeah, such a shame I've just upgraded to a 7.0 motherboard for my socket AM7 CPU.

Being less sarcastic, I would ask if 6.0 mobos are on the horizon.

what I don't get: why doesn't AMD just roll Gen6 out in their CPU, bifurcate it to Gen5, and boom, you have 48x2 Gen5s? same argument for gen5 bifurcated to gen4.

this would solve the biggest issue with non-server motherboards: not enough PCIe lanes.

I feel like what we really need is a GPU "socket" like we have for CPU's. And then a set of RAM slots dedicated to that GPU socket (or unified RAM shared between CPU and GPU)
I wonder if this will help applications like VPP/DPDK. not sure if the CPU or the lanes are the bottleneck there.
I can't be the only one let down that there wasn't some new slot design. Something with pizzazz and flare.
So I can run a full powered PCIe 4.0 16x GPU on 1 PCIe 8.0 lane???