hi. is this odd to anyone else?

ok my setup is :

amd 64 3500+
geforce 7600 GT (new drivers)
2 gb ram
windows vista home premium (64bit)

wow resolution is 1280x1024 FPS is low in town 10-15, out of town 20-30..in a building 30-40.

my friends:

core 2 duo
geforce 7300 LE (standard vista drivers for that card)
2 gb ram
vista home premium (32 bit)

he runs resolution in wow 1152x864 and get 40-50 FPS pretty much anywhere..


the systems are that much different to yield such different results?

i have a better graphics card and drivers..shouldnt i be getting better or at least the same performance?

any ideas would be great. thank you.