The specification of my desktop computer is as
Processor: AMD FX 8320, Motherboard: Asus M5A97, RAM: Kingston HyperX 16 GB (8*2), HD: 1TB WD Black, Graphics Card: 2GB Saphire 5450, SMPS: Cooler Master 650W, OS: Windows 10
Sometimes its processor fan spins faster and makes noise (especially when I use virtual machine) and after this activity the computer shuts down automatically.
I diagnosed SMPS, RAM & HD. All are working fine.
Sometimes the computer shuts down in 30 min and sometimes it works fine whole day. That’s why technician couldn’t identify the issue.
I already removed dusts and cleaned inside the cabinet using a blower. There are three fans on the cabinet (two 5mm and one 12mm). All components (Processor, RAM, HD, etc.) are about two and half years old. The processor heatsink is the same that came with the processor which is tightly fitted with processor and on board.
What can I do to prevent this behavior?
I'm no expert but i had my Phenom fan spin really fast and kept shuttung down. I was told to make sure that the heatsink was free of fluff because it makes the fan spin fast and the CPU running hot, hence the shut down. It was full of fluff and now i check and clean it out regulaly.
Then you should run a malware/mining scan, and probably uninstall all old 3rd party apps.
Check all your privacy/access settings in every installed app.