[SOLVED] ASRock X399 Fatality Multi GPU Question

Hardware Hub Motherboards
1

So I have kind of an odd GPU setup for a machine that I built recently for rendering.

PCIe 1: 1080Ti Hybrid Cooled
PCIe 2: 1080Ti Hybrid Cooled
PCIe 3: 1080Ti Hybrid Cooled
PCIe 4: Titan X Pascal (Aircooled)

My current situation is that all the GPU’s are recognized just fine, but I can only get a display output from the top card. I need to run my displays from the bottom Titan X card, but I’m not getting a single signal form it, either during boot or when in my OS.

Anyone have any ideas on how to get it to work? I’ve done this fine on another machine, but with the Threadripper board it really doesn’t want to do it for some reason. Maybe it’s a simple bios setting? Any help would be much appreciated.

I’m on BIOS version 2.0 at the moment.

(Please don’t reply telling me to move the cards around, the whole point is that the bottom one gets more air.)

2

You could try following things:

  1. check your bios for setting boot card.
    Didnt see anything in manual but there is still a chance
  2. in BIOS set “Launch Video OpROM Policy” to UEFI or disable CSM entirely
  3. if you are using linux add “fbcon=map:3” (or whatever works for the Titan X) to boot parameters
    To find correct number pair output of “for i in 1 2 3 ; do udevadm info -n /dev/fb${i}; done” with lspci
    This will not help with boot screen but console will be redirected to Titan X once the driver is loaded
    I dont know if any configuration will be needed for X as i am using custom xorg.conf

As i dont own this board, or any threadripper build, 1 and 2 are guesses based on my experience with Ryzen.

1 Like
3

I didn’t find a boot card setting at first glance. (But I might search if such an option exists digging deeper down.)

But both setting the Video OpROM to UEFI and Disabling CSM both worked.

Thanks for the suggestion, you made my day. :slight_smile: