OK, before doing anything further, back up all files that are important to you (safety measure).
You can try System Restore to restore your system to the state where everything was known to work.
Start > All Programs > Accessories > System Tools > System Restore
- Restore my computer to an earlier time
- Next
- Choose the date/time just before you tried out the "NVIDIA graphic thing".
- Next
And follow the prompt.
Please let me know if this helps.
__________________
-------------------------------------------------
Primum non nocere
-------------------------------------------------
|