Motherboard PCI spacing and GPU sizes - why so poor compatibility?

Are there any motherboards out there that have proper PCI slot spacing? I suspect the product doesn’t exist, but I would really like an XXXL EATX format of some sort, with effectively wasted PCB space, but for the sake of proper spacing and maybe better cooling to boot.

Have any of you come across anything like that? How are you all dealing with space issues, any other solutions to risers/cables, or you just make sure to buy physically smaller GPUs?

I recently bought a pre-built PC with Gigabyte TRX40 Designare motherboard and Gigabyte RTX 2070 Super GPU and my plan was to consolidate my other gaming PC (with a 1080Ti GPU) and a file server (with a hardware RAID card) into that new PC and use VFIO.

Well, turns out the Gigabyte 2070 Super is 2.5 slots wide, so it covers an additional PCI slot, and my old 1080Ti that I was about to gut from my earlier gaming PC is also 2.25-2.5 slots, so would also cover an additional PCI slot.

I went with Threadripper so I can get all the additional slots and PCI lanes, only to be defeated by silly physical sizing. Out of 5 PCI slots, I’m down to 2 due to GPU sizing, maybe 3 if I count the x4 slot, but I have no use for it at the moment.

Have I missed something obvious or does the industry just not cater to folk running 2+ top tier GPUs with the rest of PCI slots still usable?

Ideally I’d want to use all 4 physical x16 PCI slots on the motherboard, but it looks hopeless so far with the GPUs I have.

I am buying a PCIe riser/cable in hope of salvaging one of the covered up x16 slots, but as the male connector is straight, I’m not sure it’ll fit under the protruding GPU shroud.

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Maybe put waterblocks in place of the air cooling on them? Kind of a pain but IDK what else?

A lot of boards tend to interleave m.2 slots in between the PCI-E slots to help with that. Buildzoid did a round up of TRX 40 boards if you’re looking for alternatives.

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Custom watercooling is your best bet if you want full access to all pci-e slots.

Not really the motherboard manufacturers fault imo.
Blame nvidia and amd for not making their silicone more efficient.

Thanks - yep, watercooling might help, but I don’t think I’m prepared to tinker that much… yet. Will try raisers first, if I can squeeze them under the shrouds.

I think the Gigabyte TRX40 Designare is basically the same as most other TRX40s, it is XL-ATX - I haven’t come across anything bigger to be honest. It does have M.2 slots in-between PCI slots, but still not enough space.

I’m just flabbergasted that it seems accepted and not really mentioned anywhere, feels like it should be flashing in red in product descriptions when buying - i.e. this GPU is 2.5-3 slots wide and will likely steal an additional slot on 99% of motherboards.

I do feel like mobo vendors are partly at fault, they could just make them bigger and give people options. There are huge workstation mobos of course, dual-socket etc, but I’d be after the same features and cost as on the TRX40, just more spacing. It seems like an unfilled product niche.

There already are big cases on the market that could easily accommodate bigger mobos (mine’s Fractal Define 7 XL - plenty of space left if only I could stretch the darn motherboard)

Thanks for your ideas!

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Because standard form factor is dual-slot, and 2.5-3 slots are AIBs pushing outside standards for power and thermal headroom on their designs. If you want to fit multiple cards snug then you buy dual-slot cards.

That said there are a lot of standard ATX boards with three slots between PCIE1 and PCIE2, both for X570 and Z490.

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The spacing looks pretty standard.

Maybe change the GPU’s shroud?
Prolly cheaper than a waterblock / closed / custom loop?

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