OP here. After messing up my AMD drivers, The closest I can get to my 655MH/s is 620M/s.
I'm using drivers 11.10 and SDK 2.4, with clocks at 1020core and 370 memory.
I've tried playing around with clocks, but barely a difference, same with GUIMiner Pheonix flags(-k phatk VECTORS BFI_INT FASTLOOP=false AGGRESSION=10)
Should I just re-install my windows 7(even tried service pack 1)?