I'm not sure what's caused it. I haven't changed any system settings. The only thing I've done that may have broken something is updating my software.
My update was:
upgrade linux-generic-hwe-20.04:amd64 5.8.0.48.54~20.04.32 5.8.0.49.55~20.04.33
upgrade linux-image-generic-hwe-20.04:amd64 5.8.0.48.54~20.04.32
upgrade linux-headers-generic-hwe-20.04:amd64 5.8.0.48.54~20.04.32
upgrade linux-image-extra-virtual:amd64 5.4.0.70.73 5.4.0.71.74
upgrade linux-image-generic:amd64 5.4.0.70.73 5.4.0.71.74
upgrade linux-libc-dev:amd64 5.4.0-70.78 5.4.0-71.79
upgrade libseccomp2:amd64 2.4.3-1ubuntu3.20.04.3 2.5.1-1ubuntu1~20.04.1
upgrade nomachine:amd64 7.3.2-3 7.4.1-3```
Removing nomachine did not solve the problem.
It was far worse before, I'm not sure how to describe exactly, but my entire screen's UI was glitching out. So I rebooted and that stopped, but now the terminal text looks like this:
I haven't changed any terminal settings. This seems to be occurring in the entire OS. Here is another example:
Not sure how to go about troubleshooting this? I don't have the time to reinstall the OS, nor do I think I should have to because this is just ridiculous and shouldn't happen. I'm not aware of anything I've done to make the system unstable.
Edit
Earlier I also tried booting the PC. It failed and got stuck on some command in a terminal (didn't manage to take a photo of what it said).
So I rebooted into recovery mode with both available kernels. I was getting strange glitches like this:
That didn't work. So I rebooted the PC normally, and now I somehow logged in fine. Now I'm getting popups saying to report a system error. It says this:
Environment
- Ubuntu 20.04.2 LTS
- GNOME 3.36.8
sudo lshw -class display
*-display
description: VGA compatible controller
product: Xeon E3-1200 v3/4th Gen Core Processor Integrated Graphics Controller
vendor: Intel Corporation
physical id: 2
bus info: pci@0000:00:02.0
version: 06
width: 64 bits
clock: 33MHz
capabilities: msi pm vga_controller bus_master cap_list rom
configuration: driver=i915 latency=0
resources: irq:33 memory:f7800000-f7bfffff memory:e0000000-efffffff ioport:f000(size=64) memory:c0000-dffff
I also did MemTest86, which passed with 0 errors.
Let me know if more details are required.