Mmm . . . said in a thoughtful way. I've loaded the graphics card and at first it doesn't look much different.
One of the symptoms is this shifting area of mysterious - nothing. Not kidding. I've seen (groan, or not seen) it before. It's like a ghost in the room - you see it to one side, but when you look it's not there. If I hadn't been aware of it before, I'd think I was imagining it.
The familiar Nvid menu however does allow more adjustment of the picture. Gamma has got rid of the white haze at last.
After that, and another session with eyeglass and the phase control on the monitor, I've got it to what might, with a bit of imagination, look fair. At best.
Now, with data going through a low-end, but respected graphics card, it can only be the signal from the MB causing the commonality. To me, it goes against the grain to not turn off the other system's output electronics. It many have done so, but I'm not sure how to find out. There's certainly not anything coming out of the old VGA plug.
I have a feeling an Asus MB is about to appear on my doorstep.