Try sharing a Web Speccy report so we can see a little about this unknown PC. If it's a desktop supply the make, model of the power supply.
Recently I've been getting this problem where my screen goes black after playing a video game for a while. Before the screen goes black, the computer starts making a clicking/scraping sound and the humming noise starts cutting off. After this, the screen goes black and says "No Signal". I can still hear the audio but the screen is black.
The noise: https://www.youtube.com/watch?v=JBtTGQIiMSA