So you have the Omega release, drivers are most certainty the current.
This is what I use most of the time with many users and it often works; Courtesy of ComputerTipsFree
Fix 2: Replacing nvlddmkm.sys in your system file – Display Driver Stopped Responding
This is a well-known fix for this issue. During the installation of most graphic drivers in Windows Vista, an old version of nvlddmkm.sys is copied into C:\Windows\System32\Drivers and not the current one in the install. As a result the new drivers are attempting to access the file dated 2006 instead of 2010. To fix this,
nvlddmkm Stopped Responding – Step 1: Download and install the latest nvidia graphic driver.
Step 2: Then go to C:\Windows\System32\Drivers and rename nvlddmkm.sys to nvlddmkm.sys.old.
Step 3: Go to nvidia directory (usually in C:\Nvidia or C:\drvvganVidia) and find the file nvlddmkm.sy_.
Step 4: Copy the file to your Desktop directory.
Step 5: Open cmd.exe by going to Start -> type cmd in the search box and hit enter.
Step 6: Change the directory to Desktop by typing chdir Desktop.
Step 7: Then, type EXPAND.EXE nvlddmkm.sy_ nvlddmkm.sys. Or,
expand -r nvlddmkm.sy_ nvlddmkm.sys
Step 8: When the expansion is complete, copy the new nvlddmkm.sys from your Desktop to C:\Windows\System32\Drivers
Step 9: Restart your computer and the problem should be resolved.
You will probably realise that any uninstallation and reinstallation of nvidia drivers will not remove the old nvlddmkm.sys file and will not overwrite it with the latest version. You have to do it manually. Nobody knows why but who cares as long it’s fixed.
Fix 3: Replacing atikmdag.sys in your system file
This is also a well-known fix for this issue if you have an ATI graphic card. During the installation of most graphic drivers in Windows Vista, an old version of atikmdag.sys is copied into C:\Windows\System32\Drivers and not the current one in the install. As a result the new drivers are attempting to access the file dated 2006 instead of 2010. To fix this,
atikmdag Stopped Responding - Step 1: Download and install the latest ati graphic driver.
Step 2: Then go to C:\Windows\System32\Drivers and rename atikmdag.sys to atikmdag.sys.old.
Step 3: Go to ati directory (usually in C:\ATI) and find the file atikmdag.sy_.
Step 4: Copy the file to your Desktop directory.
Step 5: Open cmd.exe by going to Start -> type cmd in the search box and hit enter.
Step 6: Change the directory to Desktop by typing chdir Desktop.
Step 7: Then, type EXPAND.EXE atikmdag.sy_ atikmdag.sys. Or,
expand -r atikmdag.sy_ atikmdag.sys
Step 8: When the expansion is complete, copy the new atikmdag.sys from your Desktop to C:\Windows\System32\Drivers
Step 9: Restart your computer and the problem should be resolved.
You will probably realise that any uninstallation and reinstallation of ati drivers will not remove the old atikmdag.sys file and will not overwrite it with the latest version. You have to do it manually. Nobody knows why but who cares as long as it’s fixed.