Here are the specs for your HP Pavilion g6-1c40ca Notebook Computer. Based on the specs, this model shipped from the factory with Windows 7 Home Premium 64-bit installed.
Please indicate how you "reinstalled windows 7 64 bit on it." If you used your set of HP Recovery Discs, all drivers and software should be installed correctly and functioning. However, if you used a plain Windows 7 installation disc and generic driver downloads, certain HP features may ail to work as expected.
Please indicate what drivers you used, where you got them, and what devices (if any) are "unknown" or have a yellow triangle in the Wndows "Device Manager"
Please send KUDOs
