[rkagerer]

Now we're talking - thanks!

(ps. I don't suppose they make a "supersized" version of that board with a gap beside the first one or two GPU slots? So you can install a couple double-width cards without losing the underlying slots? Or a good source for a single-width, high-end GPU like the Inno3D RTX 5090 iChill Frostbite Pro?)

[michaelt]

The card in the bottom slot can overhang the board, if you only need to add a single multi-slot card.

Beyond that point you're probably looking at getting a server. Boards like the X9DRG-OF have eight dual-width slots, and you can get them in a quadruple-power-supply configuration - which you'll want when you add up the power consumption of a bunch of GPUs. Anything rack-mount will be very noisy though.

Another options is a cryptocurrency mining style 'open frame' system with PCIe risers. Google that and you'll find some crazy setups enthusiasts have posted to reddit.

Or you can just run something in the cloud - you can buy a lot of cloud time for $6000.

[rkagerer]

Thanks. I like that Asus board but research turned up some reports of potential stability issues, especially if running Proxmox. Any thoughts on the ASRock WRX90 WS EVO as an alternative? I can probably live with the reduced NVMe count by using an NVMe RAID card like that Areca one.

[PeterStuer]

You would typically use good riser cables for that. Spacing out the MB pcb itself is not an effective option.