I played Half Life at 1280x800 with high settings and it worked fine from what I can tell other than the glitch in the engine that screws up the game.
I can play counterstrike:source at 1680x1050 with high settings fine and at...
Z70v pre-refresh. It's unfortunate that this refresh thing came about right when mine arrived, but but I am already playing Counterstrike:Source on high settings and am half way through HL2.
It's an amazing machine.