Monitor all fuzzy when coming out of standby

[FeFiDoh]

The other day when I turned my PC on, my primary screen, an Asus PG279Q had all fuzzy text and image on the login screen. I restarted PC and it seemed to fix itself.
Today I went downstairs and when I come back up and moved the mouse to get monitors out of standby, my secondary screen, a Dell, has the same problem.

Any ideas what this is?

 

[Habakkuk]

If the card is fine, this has to be a graphics driver issue.

Update the graphics drivers, to beta ones if they're available if that doesn't sort it.

 

[liveid]

or go back to a previous driver set if theres ben an update

PS double check the cables to the screens they work loose!