I didn't suggest you use Teamviewer, just trying to clarify what Mo20 said before, Mo20 suggesting you use Teamviewer without any output on both card, and I told you will get small screen because those cards will not produce the right resolution.

I suggest you use a dummy output (HDMI or whatever adapter) in one of your cards with a small Hahsrate. Adapter only, don't need to connect to monitor. Have you done what I suggested before?