To me this is the typical failing PC. But there's so little detail so you may have to share a lot more.
For now you can try it with the cover off and check for heatsinks and fans. These must be in their proper places, work like new and not have fallen off.
Yesterday out of nowhere shortly after startup my computer froze and both screens turned white and I had to restart my computer. This morning about 30 seconds after I started my computer up and open a browser it froze, had to restart my computer. Then I restarted it and it got stuck on the menu that told me to press Delete/F2 to goto bios. Now when I try to start it up it just sits on a black screen, but it's as if my monitors are turned off (digitalport input).
I tried changing some cables around and finally got it to turn on with an hdmi cable. When I start it up, it freezes after about 30 seconds, reboots my computer, then I can login again for 30 seconds. It will then just turn my monitor black and the computer stays on but I have the orange light where I turn my monitor on, as if it's off.
Any ideas as to what to do

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