Got a 1080 FTW Thursday and it has been Flawless until today. Running an MSI Z board with a 6600k and 16gb of gskill running win 10. 750 watt psu. Nothing Overclocked. The build is a few months old and I was waiting on a 1080 to retire my AMD 7950. The first two days after the install was great, no issues, 3d marks outstanding, Black Desert Online beautiful. Today, system started to hang while I was playing and frame rate went to <10. I rebooted, then it immediately started locking up when running a game or benchmark. I reseated the card to no avail. During the 3d mark, I saw lots of artifacts before it froze. After a DDU and a fresh driver install, everything seemed worse. Tonight when I get home, I'll roll back to my 7950 to see. Any other thoughts or suggestions? Thanks guys!

As a sanity check, which brand and model is the "750 watt psu"?

thermaltake PSUs are not the best when providing power. You should consider buying a much better PSU to power that GPU.
 
Trust me, they're not that good. I had a 1,000 watt from thermaltake, and it would not power up my DARK motherboard, unless it continuously hit the power button numerous amounts of times, then it would finally turn on. Once I bought a higher grade PSU, the issue was completely fixed.

Time for an RMA request.......

richurd
Still think it may be PSU.

+1. Newer GPUs acquire power differently than older GPUs.

Just got an RMA for newegg. Hope they can get me a new one soon. They are still put if stock. If there is the slightest issue with a new card, I'll go all out on a psu. Seriously though, played a game for the last few hours... Flawless. Consumption can't be that much more in a 1080 vs an amd 7950, can it?

Closest micro center is 3 hours away. Any recommendations on a psu if new card still has issues? Last night I Overclocked my 7950 and ran a stress test on the system overnight. No issues.

Run something like HWinfo and see what your voltages are showing just to see if there are any noticeable fluctuations.  It isn't an end all, but if that is bad then you already know.
 
There are a number of good power supplies available.  eVGA, Seasonic, Corsair, and a few others.  The bigger issue is how much you want to spend.  Do you want a platinum rated supply?  A titanium?  People cheap out on power supplies and it is one of the single most important pieces of your build.

richurd
Still think it may be PSU.

Its not though. I have cheap ass Corsair 650Watt powersupply running the FTW 1080 fine. My PSU are so old its not even Gold, Silver etc certified. If I would guess its bronze.
Have been running with max OC for years still runs.

Corsair vs Thermaltake toughpower.  Odds are Channel Well makes them both.  Most every of these 'gaming' PSUs are made by only a handful of manufacturers and are rebranded.