Windows 10 how to regain control of both screens

You might need to download the EVGA GPU utility from their website such as NVIDIA utilities or AMD Catalyst utilities to help you manage individual screen resolution settings on each GPU card. Be warned, however, that these utilities are notoriously unstable, and can and do often cause BSODs, and Black Screens. Your best bet is to FIRST BACKUP ALL OF YOUR PERSONAL DATA TO EXTERNAL MEDIA! THIS WOULD INCLUDE YOUR LIBRARY FOLDERS FOR DOCUMENTS, PHOTOS, MUSIC, VIDEOS, AND ANY SAVED E-MAILS OR ATTACHMENTS IN ORDER TO PREVENT IRRETRIEVABLE DATA LOSS!!
Even if the EVGA utility works, it could cause system instability or worse cause it to no longer boot! Our crash experts here usually recommend removing the utility if that occurs. However, if it doesn't that may help solve your problem.

Another word of advice, if you have the ability to create Factory RECOVERY MEDIA as most computers have these days, a utility that allows you to create the media on either DVD or USB, it would be a very good idea to have on hand BEFORE installing one of these GPU management utilities. And, to supplement that it would also be prudent to take an Image snapshot of your existing hard drive using Macrium Reflect, Acronis TrueImage, or EASEus TODO free backup softwares. I like Macrium the best, but you should know they started charging for their backup software now in v7 as of March 1st. You can still download a 30-day trial for free and make your backup Image, however, after that, the software will no longer make backup images or restore a backup image already made. This could be a problem should your GPU utility crash your W10, as you'd have to pay $40 to get a license to make the software work again so you could restore a working W10 image to your hard drive. Some things for you to consider. And if you're one of the few who have already done both, more power to you! And good job.

Best of luck to you,
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