The PMU of the Sawtooth and later Macs is a little more all-encompassing than the PMUs of older PowerBooks. Newer PMUs are rather more wide-ranging, and Apple describes them as 'computers-within-a-computer'. They can be finicky, and it is reported that the Sawtooth is in the front row of those. A good start is a complete reset of your logic board, as porter writes.
Remove the Sawtooth from the mains power, and remove its PRAM battery. Leave it so not for just the usual 20min, but overnight. Then replace the PRAM battery before you reconnect to the mains. Hold in the PMU for just one press of about a second. (Don't hold it in for 40sec as you would with a CUDA switch.) Make sure that you don't handle the circuitry around the PMU, even if you are wearing a wrist-strap. Don't let the switch 'bounce', because that will count as a second press, which will flatten the battery overnight and require you to reset the MLB again. Speed of your CPU notwithstanding, I would second porter's recommendation that you revert to 10.4.11 on the Sawtooth when you have it going. If even the described treatment will not wake up your Sawtooth, you may be faced with getting hold of its HDD in Target Disk mode to wipe the HDD completely before you re-install OS X v10.4.11.
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Remove the Sawtooth from the mains power, and remove its PRAM battery. Leave it so not for just the usual 20min, but overnight. Then replace the PRAM battery before you reconnect to the mains. Hold in the PMU for just one press of about a second. (Don't hold it in for 40sec as you would with a CUDA switch.) Make sure that you don't handle the circuitry around the PMU, even if you are wearing a wrist-strap. Don't let the switch 'bounce', because that will count as a second press, which will flatten the battery overnight and require you to reset the MLB again. Speed of your CPU notwithstanding, I would second porter's recommendation that you revert to 10.4.11 on the Sawtooth when you have it going. If even the described treatment will not wake up your Sawtooth, you may be faced with getting hold of its HDD in Target Disk mode to wipe the HDD completely before you re-install OS X v10.4.11.
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