Sometimes i hear ''click'' from my pc?

HI, sometimes i hear ''click'' from my pc but only once , and it happened to me about 2-3 times in this month, i havent noticed it before. Could it be something serious ? I dont have any crashes , my fans are working fine , and all hardware is detected. I can't afford for a new hardware , plz help

thnx

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So i suppose i dont have to worry about it??

thnx

Best Answer - Chosen by Asker

in SMPS Powerful capacitor placed these holds power after sutdown also , if you touch these you may get heavy shock even system is unpluged . so when capacitors get discharge they may click sound. its normal, dont worry.