After years of trouble free use yesterday my XFX R9 390 stopped working with two 1440p monitors. At first my computer black screened a few times while video editing, as if it was over heating and the display port on the graphics card failed. I checked to make sure the fan was going 100%, but it didn't even seem hot. It was strange. I decided to update my radeon graphics driver and a windows update (I don't recall the order, but my computer pulled down the dreaded Windows October Update).
For testing purposes I was able to swap my graphics card out for an old Radeon HD5450. The HD5450 was able to run multiple monitors in windows 10 no problem... So I think my R9 390 graphics card maybe starting to fail now.
I also tried running two monitors using one on the HDMI port. Same immediate black screen crash after bios loading.
FYI for other troubleshooters out there... yesterday I started to black screen crashes while trying to edit on a single monitor. I confirmed the gpu fans were running 100%... after it happened a few times in a row I declared the graphics card dead. In hindsight the symptoms I've listed above were the beginning of the end.