I'm really not sure what's causing this, I've never had this problem with any other mmo or game and I've only been having it with ESO since I came back a couple of weeks ago - last time around never experienced this.
Basically, after a few hours play and without warning, my screen will go entirely black. I'll still hear audio, but not see a thing. Alt tabbing doesn't work, neither does CTRL+ALT+DEL. The only way to 'reset' seems to be switching my computer off and back on again.
Could it be a VRam memory leak? I'm running an R9 290X so the card is more than capable of running this game.
Allow cross-platform transfers and merges