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Troubleshooting the Power Mac G5: Power supply noise

Troubleshooting the Power Mac G5: Power supply noise

An issue with noisy power supplies that we reported more than a month ago is continuing to generate numerous complaints on Apple's discussion boards, with little response acknowledgement from Apple's customer service department.

As we previously reported, the problem generally manifests when Processor Performance is turned to Highest under Energy Saver/Options and the computer is idle. A recurring buzz/beep sound is made. If Processor Performance is turned to Automatic or Reduced, the noise is quieter, but still noticeable to some discriminating ears.

Oddly (or perhaps not) the problem disappears when iTunes' visualizer is turned on for many users.

A thread on Apple's discussion boards pertaining to this issue contains nearly 600 posts.

MacFixIt reader Craig Hein writes "I have had this problem since the day I received my 2x2 G5 in late September. Apple has be unable to offer any solution other than to replace the power supply, with no guarantee that the replacement will solve the problem."

"Furthermore, I am also afflicted with the problem where the computer goes into an unrecoverable sleep and the fans ramp up to full blast, so that upon returning to the room where I left a sleeping computer, I hear the whoosh of all fans blasting full speed. The only way to stop them is to hold the power button for 5 seconds to shut off the computer."

The most widely reported successful repair procedure involves replacing the G5's power supply unit. Customers have been hit-or-miss in their success obtaining this repair from Apple.

If you are noticing similar issues with your G5, or have had success fixing the problem with Apple's help, please let us know at

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