I have a 144hz monitor but inside the display options i only see 144.01hz and when i select it my monitor goes black randomly for a few seconds, and it happens a lot. For example i am browsing the web and my screen goes black for 2-3 seconds. After a minute or two it happens again and so on. I am using 120hz right now and its working correctly. I use the open source amdgpu driver with my rx 6600 on fedora workstation 40. Ive got the same problem on wayland and on xorg too.
Sorry I don’t have a solution but adding a “high-five” here.
After applying the latest AMD GPU drivers and kernel from the software center, one of my monitors refused to run at the top refresh rate of 75hz. I had to reduce it down to 60hz to keep it from black screening.
Also have a AMD 6800xt card running F40 on 6.10.10-200 kernel.
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Sometimes the gpu is not capable of properly syncing with the available speeds of the monitor. The 144.01 is quite acceptable since even monitors that claim to be 60 Hz compatible often run at something different such as 59.97 or so.
If the monitor works well at 120 then I would be satisfied. Your eyes probably cannot tell the difference between 144 and 120 refresh rates anyway.
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So maybe it is a driver or kernel problem? I hope they fix it someday.
I am thinking it may be the gpu. The RX6600 is not the newest gpu though not at all bad. I have not checked the specs in detail but AMD claims hdmi 2.1 and DP 1.4a.
It also may be the cable between the gpu and the monitor. Some cables cannot support the newer and higher specs.
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I am having this same problem except with 120hz. My monitor supports 144hz, but its not even showing as an option.
When I run anything higher than 60hz, the monitor blacks out every few seconds. If I disable VRR on my monitor, the issue stops. So seems to be related to variable refresh.
It’s not the card or the HDMI cable as I dual boot Windows and I can run 144hz just fine.
I am running FC41, fully updated. I have a Radeon 7800 XT.
With several RX 580s, I found 4K@60Hz over HDMI no matter the cable, distance, OS, motherboard, PSU, or any other reasonable factor unstable unless I reduced the bandwidth of the resolution (reduced-blank). I haven’t seen a downside to reducing the bandwidth everywhere with CVT-RB and imagine it’d probably fix this with higher refresh rates.
Something like this kernel boot parameter:
video=HDMI-A-1:3480x2160MR@60
M generates the modeline regardless if it doesn’t exist in EDID, and R reduced-blanks it to reduce the bandwidth. Number after @ is the refresh rate you want (should be native like 120 or 144 but can be higher/different if you know what you’re doing)
I think it’s DP-1 (no A) for DisplayPort, but you can get the exact name through proptest or something else (not xrandr). Set the kernel option in GRUB, reboot, and check resolution lists after.