Arch Linux

dindon

Member

Registered: 2015-07-22

Posts: 5

[workaround] Can't use displayport output source of GPU

Hi,

I just purchased a new monitor for my desktop PC with two input source : DP 1.2a and HDMI 1.4 and I can't get the displayport working on Archlinux.

I've got:
- monitor: xg2703-gs
- GPU: nvidia GTX 1070 with 3 DP 1.4 and 1 HDMI 2.0b ports
- kernel: core/linux 4.15.15-1
- driver: extra/nvidia 390.48-3
- lspci -vv -s 01:00.0
- Xorg.1.log
- dmesg
- xrandr -q --verbose output

I've set a BIOS parameter to use the GPU on boot. It worked fine with previous monitor. I think it was set by default when I bought the motherboard.

Here is what I've tried :
- plug DP only from GPU to monitor, turn on computer → I get black screen with "no signal" message on monitor
- plug HDMI only from GPU to monitor, turn on computer → works almost fine, I can't use refresh rate higher than 60Hz
- plug both HDMI and DP cable, turn on computer, the HDMI output is used, I can't switch to DP with xrandr (see xrandr output above)
- reboot with vfio passthrough modules and start my Windows gaming VM : both HDMI and DP ports works fine

I'd really appreciate any input to help me troubleshot my issue.

Last edited by dindon (2018-04-21 20:32:20)

Buddlespit

Member

From: Chesapeake, Va.

Registered: 2014-02-07

Posts: 501

Re: [workaround] Can't use displayport output source of GPU

does the monitor have a "dp or hdmi" or "source" option/switch?

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Hw-Probe

dindon

Member

Registered: 2015-07-22

Posts: 5

Re: [workaround] Can't use displayport output source of GPU

Yes it has one, but playing with it doesn't solve the issue.
I figured just now that this isn't OS related at all since I have no output on the screen from boot.

I did some voodoo since, plugging all display ports one by one, and it seems that, on boot, my GPU has its output set on one of the 3 displayports only, somewhat randomly.
This means every time I reboot I need to figure out which displayports is being used... Really annoying, but hey, it's working and its not Archlinux related.