I bought a pre-built computer that has an i9 9900k and rtx 2080ti. I've had it since 2018, and it constantly crashes whenever I try to play graphic-intensive games. (Sometimes not even ones with good graphics.) I've tried cleaning out my pc and using msi afterburner's scan and test, where it says it's only 27% confident in the settings it chose. When games crash, they usually show bright lights/artifacts flickering around the screen, or black diagonal line flickering, and these are always followed by the game freezing up or crasing. Does anyone know what could be causing this and how I could try to fix it?