Graphics are broken after suspend to RAM

OS: Manjaro Linux
GPU: AMD RX 580 8GB, amdgpu drivers.
DE: KDE Plasma 5.14.4
Kernel version: 4.19.8

When I wake my computer after suspending to ram for more than a couple of minutes, it shows corrupted graphics onscreen and is unresponsive. I can still ssh in to reboot, so the system is still working correctly, but the GPU is just outputting... that.

This does not occur after suspending to disk, and does not occur on kernel 4.14.87, but I need to use 4.19 for other reasons.

I have a known-working NVIDIA GPU to troubleshoot with if necessary, and I was planning on upgrading my CPU, mobo and RAM anyway, so if it's bad hardware it's not too terrible of an issue.

I've been searching variations of "corrupted graphics after suspend to ram," but everything I could find either occurred after suspend to disk, or only corrupted certain things.

Edit: dmesg is filled with this:

[27954.516395] amdgpu 0000:01:00.0: couldn't schedule ib on ring <gfx>
[27954.516528] [drm:amdgpu_job_run [amdgpu]] *ERROR* Error scheduling IBs (-22)