Okay this is the latest 7 series driver for your card (in case you dont have it already)
NVIDIA DRIVERS 195.62 WHQL
Download it somewhere like your desktop where you can access it easily.
Also download DriveSweeper here and install it before you follow the rest of this advice.
Guru3D - Driver Sweeper (Setup) download from Guru3D.com
Next, type
msconfig into your windows start search box. Run the
system configuration tool when it appears in the startmenu.
Once open, select the Boot tab and at look at boot options.
Check the Safeboot box, click apply, OK then restart the pc.
When your back in your desktop in safemode, open the start menu again and type
device manager in the search box. Open device manager once it appears in your start menu.
In device manager look down the list of components for
Display adapters. Expand it to show your 7600GT. Right click on it and and select
uninstall. The unistaller may ask you if you want to delete driver software. Say yes and wait for your drivers to be taken off.
Once finished, restart the computer and let it boot up again into safemode. When your back to yourdesktop, run
Drivesweeper. You will see a window with a list of driver manufactures and driver types. Select
NVIDIA-Display and click on
Clean at the bottom.
A popup window will as you if your sure you want to continue. Say yes and let it clean out residue driver traces (usually in system32 folder and the system registry).
Drivesweeper should automatically ask you to restart the computer once its finished.
After your computer restarts, run the Nvidia Driver Installation you downloaded above. Install it but this time, before you restart your computer, click start and run
msconfig again. Go back to Boot tab and uncheck safeboot so your computer starts in normal windows mode. Apply and restart.
You should be good to go when it starts up again. You can access the NV Control panel by rightclicking your desktop. Run it and set your display to your preferences. The control panel usually automatically sets your screen resolution according to your monitors native display settings. Hopefully this should sort out the prob. Let us know how you get on or if you run into any problems.