[rescue] Help the ailing Frankenmac

Bill Bradford mrbill at mrbill.net
Mon May 12 09:21:02 CDT 2008

On Mon, May 12, 2008 at 08:32:56AM -0400, William Enestvedt wrote:
>    I thought the CUDA button only cleared the power management settings.


"The Power Management Unit (PMU) on the Power Macintosh G3 computers, Power
 Mac G4 (PCI) and Power Mac G4 Cube is known as the "Cuda button". In the
 later models It is identical in function and appearance to the PMU.

 Resetting the Cuda or PMU also resets date and time settings. After the
 reset, on some Power Macs, the system clock is set to 00:00, 01 Jan 1904
 for computers with Mac OS 9 or 00:00 (GMT), 01 Jan 1970 for computers with
 Mac OS X. 

 The PMU is a microcontroller chip that controls power functions for the
 computer. The PMU is a computer within a computer, as it has its own
 memory, software, firmware, input/output, a CPU, and more. Its function is

    * Tell the computer to turn on, turn off, sleep, wake, idle, etc.
    * Manage system resets from various commands.
    * Maintain parameter RAM (PRAM).
    * Manage the real-time clock. 

 Over time, the settings in the Power Manager may become unusable, which can
 result in operational anomalies with the computer. Examples include not
 turning on, not waking from sleep, or not seeing devices plugged into the
 USB and FireWire ports, among others."


Bill Bradford 
Houston, Texas

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