I'm thinking it overheated. Since no details are given (laptop, desktop) I have to be generic in my answer. Try cleaning it with canned air (so many YouTubes on how.)
Bob
Hello I have a major problem with my pc
Everytime I skype and I play a game with my friends my pc goes crazy. Let me explain:
1. Without warning every program stops (skype,steam...) and I get ''Has stopped working'' error for each one of them.
2.All text (from word,chrome or desktop) begins to shiver and changes color fast.
3. I cant open any problem and I have to shut down my pc by restarting with the button on my case.
Also everyone that is in a call with me when this thing happens ( on skype) hears a very loud static sound.
This happens when I stay for more than 4 hours on the pc or sometimes even after 2-3 hours.
I am planning to change my CPU soon. Will that help?
If no, what else can I do to fix this?

Chowhound
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