Did you uninstall your old drivers and use Driver Sweeper in Safe Mode before installing the new ones?
Please post your dxdiag file in spoilers for review.
-------------------------
Windows 7 Professional 64-bit
AMD Phenom II X4 970BE Deneb 3.5GHz CPU
ASUS M5A88-V EVO Mother Board
2 X 2GB CORSAIR XMS3 DDR3 1600 RAM
XFX AMD RADEON HD 6770 1GB GDDR5 GPU
Dell D1626HT Trinitron 21" CRT Monitor
Seagate Barracuda 160GB 7200rpm SATA3 HDD
Seagate Barracuda 250GB 7200rpm SATA3 HDD
Seagate Barracuda 2TB 7200rpm SATA3 HDD
ASUS DRW-24B1ST SATA DVD-R/RW
Corsair GS500 Gaming Series 500w PSU
CoolerMaster HAF 912 Case