Screen goes black randomly.

ASUS r9 390

When i started my PC today it keeps going black for a second before it shows a picture again. Exactly like what happens when i update my GPU drivers, or when you change resolution settings. Anyone know a plausible cause for this?

Edit: i tried uninstalling and installing a new driver. Didnt help.

Edit2: new development, Now i see a thick line across the screen with random colours near the bottom of the screen.

Edit3: tried a different DisplayPort cable. Did not help.

Edit4: the problem seems to be the DisplayPort cable. Ive now run for 20 minutes on a lower resolution and lower frameupdate frequency without issue.