Hello,
It could be a memory problem, one of the slots might be damaged (note that this is a fairly common problem in most motherboards over time, I don't know if it's due to dust, handling, or positioning...)
The truth is that it sounds more like a graphics problem to me, like drivers, overheating...
I would start by updating the drivers, if that doesn't solve anything, I would check that the graphics card is fine in every way, physically and virtually (through stress tests and similar), and if that doesn't work either, I would try formatting the system, to clean it completely and start over with updated drivers and everything else.
Best regards