I have ;
AMD Phenom II X4 965 BE (running with 3900 Mhz. with OC)
ATI HD Radeon 5850
4 Gb Ram
Getting 60-80 FPS in questing zones (Medium Settings) . But when i joined to battle in WvW fps drops 10-15 .
This is my last AMD & ATI experience. Always have the same problems, when a new game starts.