For some reason, a certain setting changes when you install the most recent update of Nvidia drivers. Mine happend to be version "66.93_win2kxp_english.exe". First, open your Display Properties and click on the [settings] tab. Click the [Advanced] button. Click on the [GeForce (etc.)] tab. Select from the side menu [nView Display Settings]. Right click the display that should be your TV (normaly either "2" or "1b" ). Highlight [select TV Format]. Click [Advanced...] at the bottom of the menu. Change "Video output format:" from [Auto-select] to the apropriate connector. Click [Device Adjustments]. Move the "Saturation" slider or just click [Restore Defaults]. Hopfully this should solve the problem.