Just a guess, but probably not that great. 1600 maybe OK, 1920 might really push it. You'll have to lower your settings in any case, not the very lowest but probably medium low (particularly view distance) and of course turn off full screen glow and death effect. I think this would work OK for PvE questing and adequate for 5-man dungeons, with a few slowdowns here and there. For raids you will have a lot of lag and it could be borderline unusable.
As I said just guessing though.