Got lower score in Heaven benchmark after GPU overclock

[khoaaa]

I got 1500 score in Heaven benchmark at stock GPU 810Mhz 1250Mhz...after i overclock it to 1050Mhz 1500Mhz...i got a score of 1200...i thought u suppose it get higher score. Using HD 7950

 

[geotek]

The only idea I can think that could be causing that is memory-related. Try restarting your computer to clear it before the 2nd test.