I have very old iMac G5 (2005, non-ALS) that recently died. Symptoms are either refusing to boot, or booting to desktop and then spontaneously locking up (non-responsive keyboard and mouse) for no apparent reason.
According to these articles, jimwarholic.com/2008/11/apple-imac-g5-power-supply-issues-and.php jimwarholic.com/2008/07/how-to-repair-apple-imac-g5.php there were known issues with bad capacitors on the MoBo and PSU on this specific iMac model. I inspected the MoBo and all the capacitors look fine. That leaves the power supply. I can't see inside the cage of the supply without removing it (that requires a pin-head Phillips screwdriver I don't own), but I did manage to measure the unloaded voltages on the connector. The 3.3V and 5.0V lines appear fine (3.32V and 5.08V, respectively), but the 12.0V lines all read 11.8V. As far as I know this is not obviously a sign of a bad PSU, but neither does it seem normal -- and the lock-ups I'm seeing could very well be due to under-voltage on some circuitry. My question is, does anyone here have experience with older iMac hardware? And if so, do you know if the slight undervoltage on the 12V line indicates a bad supply? I can find replacements on eBay, but I don't want to spend money on that until I'm reasonably sure that the PSU is the actual problem. Thanks in advance, -HJ _______________________________________________ MacOSX-talk mailing list [email protected] http://www.omnigroup.com/mailman/listinfo/macosx-talk
