Power supply ringing sound

recently turned on the power to the modem etc so i can the laptop and like i heard a ringing sound... looking where it came from it was actually the power supply

the pc works fine i think it powers on alright

why is the power supply making a sound of which i can only describe as ring ring ring

   Dunno but I wouldn't leave your computer on and unattended. PSU's are a chief cause of fires.

  Check Pricewatch for a replacement.
http://www.pricewatch.com/brands/power_supply_for_case/enermax-1.htm

More here:
http://www.bizrate.com/miscellaneous/products__SEARCH_GO--Find+it!__keyword--+power+supply__search_box--1__sfsk--0.html

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