Hi i bought a XFX 8800GTX and well it came clocked at the normal speeds 575mhz and so on, and well when i overclock it i got to 650mhz but i see no differance in performance and i play thinks like COD5WAW on high with a res of 1600x1050 so why do i not see an increase in the GPU?? can anyone help i used rivatuner and i overclocked my shader to 1400 and my memory to 900...