CNET

Apple releases Power Mac G5 Uniprocessor Firmware: Fixes no-sleeping issue

Apple has released an update to the Power Mac G5's firmware that fixes a previously reported issue where single-processor G5s refused to sleep. We first reported the problem on August 17th, noting ...
Macworld

Apple offers G5 firmware update

Apple on Monday released a firmware update for its Power Mac G5 systems. The 5.1.4 firmware update is available for download through the Software Update System Preferences pane. The update provides ...
CNET

Power Mac G5 Uniprocessor 5.1.5f1 Firmware update (#2): Problems installing, workaround

Yesterday we reported the release of the Power Mac G5 Uniprocessor 5.1.5f1 Firmware update which resolves a previously reported issue where single-processor G5s refused to sleep. We've since received ...
Ars Technica

Stumped. Can't boot to OpenFirmware on two G5s.

I have two PowerMac G5s. Both are dual CPU (2.5GHz), liquid cooled. Both have firmware locked via Apple's Open Firmware Password utility (I know the password). Both running 10.3.9.<BR><BR>One was ...