Geforce 7000m issue

Hello.

My gf asked me to take a look at her laptop, an Acer Aspire 5520. Seems the video card (a geforce 7000m turbocache) took some sort of performance hit a little while ago. The performance benchmark that comes with Vista suddenly changed from a 4 to a 2 (crappy tool to go by, all in all, but just to make the point). Frame rates also went down in games, drastically, to the point that she can't even play WoW anymore, minimum res, minimum settings.

I've tried updating drivers, video, chipset, everything, to see if that would help, to no avail. I also took it apart for a physical check...aside from a dust clogged heatsink, no discernable issues that I could find. I also minimized the options in the nvidia control panel.

A few specs:

Athlon 64 X2 TK-55 @1.88 GHz

2 GB DDR2

Some type of Foxconn motherboard

Nobody? No thoughts on the subject?