The Issue:
Upon locking the screen(or waking from suspend), the monitor continues receiving a signal from the computer that seems to be this issue. But there is another issue that has a chance of happening where the monitor stops receiving a signal entirely and refuses to come back on, no matter what I do. I can move the mouse, bang the keyboard all I want, even try to switch to a TTY, but nothing makes it come back. I'm forced to reset the PC.


Other Info:
This computer has had this issue since I've been using Gnome. I started using Fedora at F31 and left since F33. It usually had the black screen issue and would rarely have the blank freezing issue. More recently I've installed Pop!_OS and it has the black screen issue very frequently but not the blank freezing issue. Today I booted Debian 11 Bullseye from an external SSD I use to carry Debian with me. It has both the black screen and freezing blank screen issue very frequently.

On Fedora (31-33) - Both issues happen on Wayland, only the black screen issue happens on Xorg
On Pop!_OS 20.10 - Only the black screen issue has happened so far, the Wayland session is locked out OOTB
On Debian 11 - Both issues happen on Wayland, only the black screen issue happens on Xorg


System Info:
Optiplex 9020 MT, stock motherboard
GIGABYTE OC RX560 4GB
i5 4590
4x4GB=16GB RAM, 1600mhz non-ECC
Seems to be perfectly stable otherwise.

The card seems freezing according googling results of "gigabyte oc rx560 4gb freeze".
Download the latest proprietary driver?
or other according https://www.reddit.com/r/AMDHelp/com..._black_screen/
use DP to VGA? https://forums.guru3d.com/threads/i-...-black.432552/

I don't consider the proprietary drivers to be an option. They run worse, have worse support, don't support things like Wayland, and they severely restrict my distro choice. Also, being proprietary alone is very off putting.

That first issue you linked is not the issue I'm having. The second issue is also Windows related. I might try different cables, but my options are very limited since the only shared interface between my monitor and graphics card is HDMI.

DP to HDMI? (adapter) or
googling "gigabyte oc rx560 4gb freeze linux" show https://www.phoronix.com/forums/foru...ght-load/page2 not sure your dmesg output show a similar issue and a similar solution is acceptable. Post it here.

My dmesg output doesn't show any failures for AMDGPU or PCIE device 1:00.0(my radeon card) that I can find.

It turns out that I cannot test other outputs because Polaris GPUs don't support analogue output thus won't work with my DVI-to-VGA adapter. I will try connecting the PC to my TV because it also has HDMI, but my gut feeling is that it's also going to have the same issue, but who knows for sure until I test it. I'll get back to this thread if the result is a fully working lockscreen.

The issue you linked is not the issue I'm having. Their card has stability issues in general, mine runs perfectly stable under load and performs well, except for this Gnome lockscreen specific issue.

I've been playing around with my PC connected to the TV and I'm not having the issue whatsoever. While my setup is torn apart, I've noticed what the issue probably is. The HDMI cable I've been using is this scrawny thin little cable without any branding on it. So I think I need to find a new, good quality, HDMI cable. Hopefully it's just the cable that's bad and not the monitor, because my current monitor is pretty nice and I'd hate for it to have issues. I'll be back if there are any other developments, and I'll mark this thread as solved if a new cable is what solves it.

Replacing the cable with a known good cable didn't fix it. That means something with the monitor is the issue. It's an HP 25es.

The screen hdmi is too sensitive?
use a short cable or put an hdmi switch before? I have this one with separate voltage supply https://www.marmitek.com/de/anschlie...k-4-ein-1-aus/

Spending money on new hardware is not something I want to do, but I may have to try if I can't solve this through other ways.

I had another idea, but I won't be able to try it until I get back on Sunday night. I'll try setting my BIOS to use the integrated graphics as the video output and use the RX560 as a secondary GPU. My integrated graphics share only one interface with my monitor, that is VGA. Hopefully this works. I'll get back to this thread to report the results then.

Few errors in your log and perhaps a solution to clean it https://unix.stackexchange.com/quest...sector-or-chip https://forums.fedoraforum.org/showt...36#post1598336 with perhaps a positive side effect (https://www.kernel.org/doc/html/latest/x86/mtrr.html Enabling write-combining allows bus write transfers to be combined into a larger transfer before bursting over the PCI/AGP bus. This can increase performance of image write operations 2.5 times or more.)
The log you show was with a successfull TV screen boot? sometimes logs can looks different depending of the hardware attached and depending of a cold (new boot after few hours of inactivity) or warm start (reboot). personal experience with an older pc but this was with the sound card (2 cards: internal one and sound from the hdmi grafic). Preferably you identify the differences between a successful TV boot and a failed PC-screen boot.
I had already continuous freeze at boot and could solve https://www.linuxquestions.org/quest...-a-4175679184/
RAM/MTRR topic https://forums.linuxmint.com/viewtop...fc9b5#p1955434
this is other paths for searching.
Whatever: you have a cheap solution.. your TV.. thats only life threatening for you.. if others want to have access to it when you are at your PC ;-)

The log that I showed was after a non-fatal black screen on Pop!_OS with the HP monitor.

I will definitely take a more thorough look at those links about mtrr, once this heatwave passes that's making me exhausted.

I wish it were as simple as just using my TV. The color accuracy and response times are god awful on that thing.

But thank you for more research paths! I appreciate you taking the time to try and help me.

Hopefully my idea about the Intel HD output workaround works, I will get back to this thread when I get home and can try it.

I switched to using Intel HD as the primary GPU and the Radeon as a secondary GPU. I'm no longer getting a fatal freeze, only the non-fatal black screen. So that's definitely an improvement. I'll have to manually turn off my monitor now when I lock the screen because there is always a signal being sent to it. But at least I can lock my screen now and be able to log back into the session just fine.

Might depend on exactly how you installed both.

If 5 has its own partition then just delete it regularly.

Next time you run an update with grub update it will fix the loader.

What do you mean by "5"?