I know there's a topic on a similar issue already, but mine differs quite a bit:
Got an RX 460 recently and noticed that my screen seems to flicker just ONCE every couple minutes. I noticed this primarily on the desktop or while surfing. Looks like the image is 'jumping' for a brief moment. Like literally one short jump and that's it. Time between those jumps was about 30 minutes before, right now it was about 10 minutes between those.
I remember having a similar issue many, many years ago with a gfx card I can't even remember. On that card, this jump/flicker was usually right after quitting a game if I remember correctly. Figured out it was caused by the card changing its state and clocks to desktop mode (it might have been a Radeon 3870, don't know). Not sure if that's the issue here though, as clocks seem to jump around a lot according to WattMan, without causing any problems.
XFX RX 460 (passive)
Corsair HX 520W
ASUS M5A99X Evo R2.0
Samsung 2233RZ (1680x1050 @ 120Hz)
I upgraded from a GeForce GTX 750 Ti, which did not have this problem. Uninstalled the drivers, installed default VGA driver and then replaced card and installed 17.1.1