Here is the issue. Irregularly shaped black polygons, flicker across the landscape, characters, items, and any in-game object when I'm playing games. Sometimes I play for hours and no problem. It seems to start when there is a load or transition (game start, load save file, sit down, change view, enter building). There is no predicting whether it will start or not. It is seemingly random. It will not stop until another load or transition occurs, and there is no guarantee it will stop at that point either. The stopping is seemingly random as well.
The black shapes seem to adhere to the contour of the objects, sort of like chunks of textures aren't rendering, or something like that (I don't speak game design very well, apologies).
This issue started while playing the third act of Baldur's Gate 3, but since it started there, it now occurs in Starfield as well, and I was playing that game without issue for a couple weeks. I haven't noticed it on other games, but I don't have many installed to test on at the moment (not a lot of space with these two 100+ GB games).
ADDITIONALLY, when the trouble began, playing BG3, another, more rare display issue started, which was a sort of crackle of pure red, and when it gets really bad, also pure blue, pixels across portions of the screen. Even more rare, sometimes red and blue and other multicolored pixels stay flickering in fixed position, in a regular pattern.
Although these problems started during a period of high demand on the GPU and CPU during BG3, they now occur at low demand moments (sitting inside a room, pause screen, etc).
A couple of videos below capture all three issues in BG3, and the black spots and red pixels (if you look carefully) issue in Starfield.
(BG3 SPOILERS - I don't believe there are any story spoilers in this video, but if you want to err on the side of caution or keep the setting a surprise for Act 3, do not watch)
BG3 - All three issues on display. Multicolored regularly arranged pixels on main menu and gameplay, black flickering polygons on textures, red and blue pixels on loading screen visible especially in dark area toward bottom.
Starfield - Black flickering spots visible throughout, and some red pixels if you look carefully in pause screen.