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-Premiere Pro Video Editing Information FAQ http://forums.adobe.com/message/4200840
Do not count on Windows to be fully up to date when it comes to device drivers
Go to the vendor site to be sure you have an updated driver for your graphic adapter
•nVidia Driver Downloads http://www.nvidia.com/Download/index.aspx?lang=en-us
•ATI Driver Autodetect http://support.amd.com/en-us/download/auto-detect-tool
There are also intermittent reports that the newest driver is not always the best driver due to driver bugs or compatibility issues, so you MAY need to try an earlier driver version
In the source monitor, in the lower right corner, click on the wrench icon and confirm the video display is set to Composite Video and not Alpha.