Hope someone can help me out. I have a dual monitor desktop setup with one monitor connected directly to my motherboard and another connected to my graphics card (Gigabyte Radeon R9 390 8 GB Video Card):

$ lspci | grep VGA 00:02.0 VGA compatible controller: Intel Corporation HD Graphics 530 (rev 06) 01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Hawaii PRO [Radeon R9 290/390] (rev 80)

Both monitors are HP VH240a connected via HDMI.

Currently, the monitor that's connected to the graphics card is disabled when I'm running Ubuntu (works just fine in Windows 10). When it's enabled in Ubuntu, both screens work fine for 4-5 minutes and then the graphics card screen goes black, I'm not able to click anything on the other screen, and then after a few seconds everything freezes and I have to hard-reboot my computer.

I've resorted to only using one monitor for the time being when I'm using Ubuntu, but I'm confident there's a solution out there that I just can't find. I can try to reproduce the issue and share error logs if that will help with feedback. Does anyone have any suggestions?