After starting up my desktop and using it for some time, the screen will randomly go black. I'm not doing anything specific when it does, and the time between start-up and the screen going black can vary from 5-10 minutes. At this point I'm forced to manually restart the computer. Upon reboot, the screen will remain black, and the GPU hums loudly. It can take several reboots for the GPU to stop humming and get the screen working again, after which it may go black again after a random interval, or remain functional for ~3 hours before I power down.
My desktop was built by a friend, about 5 years ago. The graphics card is a NVIDIA GeForce GTX 275. I have updated its drivers after this started happening.
This seems to have started happening after I briefly used streamtv a couple weeks ago. I was careful not to click anywhere unnecessarily. Malwarebytes scans have revealed no findings.
Any help or advice in resolving this issue would be greatly appreciated! Thank you!