Dual video causes many problems
-link to why http://forums.adobe.com/message/4685328
-HP Fingerprint/Password conflict http://forums.adobe.com/thread/911575
Premiere Elements 12/12.1 on Windows 7 (assumed 64 bit)
Have you updated 12 to 12.1 yet? If not, please do that.
If you determine that you have the latest driver version for your video cards/graphics cards and they are optimally set and the problem still persists, please consider deleting the BadDrivers.txt file. The following gives the details for the location of the BadDrivers.txt file for your Premiere Elements version and tells you how to enable Folder Option Show Hidden Files, Folders, and Drives so that you can see the path to this file.
Is this a "it worked before but not now" or "it never worked before" issue?
We will be watching for your follow up.