I have an HP Elitedesk 800 g1 sff with an integrated Intel Xeon E3-1200 V3/4th Gen graphics card. I've been using Ubuntu on this system for years without problems, but am now facing an awkward situation:
- I have Ubuntu 20.04 on a MBR disk (2TB) and it works flawlessly
- I clean installed 20.04 on a GPT disk (3TB), and the system is responsive until after login - I can enter username and password, select to restart etc. But when I'm logged in, the screen starts flickering and nothing works. I can only go to console and reboot.
- If I run Ubuntu in recovery mode (640*480), everything works.
Considering that the same version (20.04) on the same system works flawlessly with MBR but doesn't work past login on the GPT/UEFI install, I'm assuming that's where the problem lies. I updated the BIOS to the latest version, with no results.
I tried tinkering with the graphics drivers but to no avail, so now I'm back to a clean install not knowing what to do.