It's definatly the integrated videocard.

It's highly likely it uses swap files as memory as well. Next to that they usually have shitty core speeds and just overall awful awful performance. (There -are- decent integrated videocards out there, but many are purely for 'desktop' usage really. :P )

Getting a cheap 128mb standalone agp card (or pci-e, depends what slot you have), some... geforce 6kish or something, should be cheap as heck. But should do the trick.. for one isntance you won't need GTX or GTS versions or the likes, the standard cheap model versions should be plenty to run wow at 30+ with 2gb of ram already present.

Ram+cpu seems more then fine. even if it's a dual cpu system (instead of dual-core), 1.6Ghz is plenty to run wow from.

(Shouldn't have to be more expensive then 40ish USD)