(I hadn't seen your gfx card guess when I was making that last reply.) Unsurprisingly, the updated gfx drivers fixed the problem.
I will say again that I never saw this issue at all prior to the Fall Creator's Update installation. I'd been monitoring GPU metrics (incl voltage) for a year...
I disabled nearly everything on the list and the stutter was still there, then I disabled:
GPU [#0]: NVIDIA GeForce GTX 1080 Ti
and the stuttering was gone. It is the monitoring of the GPU that is causing this issue, it seems. And, again, I had HWiNFO64's CPU and GPU monitor graphs running...
Actually -- I came back to update. I tried loading the frightening looking EVGA Overclock Monitor Suite or whatever it's called and turned on it's own set of system tracking graphs (it supports quote a few metrics), and what I saw in-game was basically the same that HWiNFO64 was doing -- the...
This seems to have happened coincidental with upgrade to Windows Fall Creator's Update to Windows 10 (Redstone 3).
I have a top-end gaming PC (i7-6700K 4.2GHz, EVGA GTX 1080 Ti FTW3 Gaming, ASUS Z-170 Pro board) and I've been playing the game No Man's Sky for over a year. I get 60fps locked...