Suggestions?   Setup: I have Two EVGA systems setting next to each other, a X58 with a i7-980X and a X299 FTW-K with a i9-9980XE, They Both have Corsair AT1200 PSU's. Run through a Switch deck 4K HDMI switcher to a Samsung HD TV.  
  
My Issue: On the X299, the 2080 super goes to a black screen randomly, and then back to normal,  
I cannot make it happen loaded or unloaded, even pushing it with Furmark, it's completely random, without cause, or reason. It is Not a heat issue, and I assume not a power issue since I can run furmark, and stress test the GPU without it stopping. This same card does NOT do this in the X58, I also have a 980 ti, this card does NOT do it in the X58, or the X299, It's only the 2080, and only in the X299? I have updated drivers, gone into windows and disabled sleep, and set power level to max, The X299 is now siting In the case, I had an X58-4 way, I just sent in for No display, GPU's worked in another system, so I assumed it was the board, RMAed, and got the X299, as a replacement. Normally I consider myself a good troubleshooter, and have the equipment to move around parts to confirm my conclusions....But this time I am just Stumped. I could Just leave the 980 ti in the X299, and the 2080, in the X58, but I was wanting all the newest, fastest, mostest,  Parts in the same box. Besides doesn't the 980 use more power than the 2080, The 980 ti has two 8 pin power plugs and the 2080 super has a 6 and a 8. So I really cannot blame the AT1200, witch has run Two 980 ti's in the past, in SLI. I can't even call tech support until I get a better handle on what is happening here, They would think I was nuts.  Everything seems fine at 68-70 fps in a Heaven Benchmark on a 4K Display, then it just goes Black for a second or two and then back to Normal, Another strange thing, is is will do it too, if I am just reading e-mail, on AOL.  And it's only the 2080, on the X299.  I do have another 2080 super in my Daughters computer, I may swap them out and see if the problem moves to her X58, If I don't give up, and decide to live with the 980 ti.

Resolved, But i don't know how; I took the 2080 super out of my Daughters computer and put it in mine, and mine in hers, and they both worked, I swapped them back and my black screens returned, so I left mine in her computer.... Have no idea what's going on, but I will let them stay, where they work. As a Final Test, I put both in my computer in SLI, or rather NV-Link, and had no issues, so I know it's NOT power related.