Currently it is almost entirely unresponsive. I came to wake it from sleep a few days ago and it refused to wake. It is totally unresponsive to the power button on the Apple Cinema display and when the power button on the front of the tower is used the button lights up blue and then goes out. There is no fan activity or other sign of life. There is no burned oder or evidence of anything charred. It is a dual 1.42 MDD FW800 machine with AGP graphics. Model: M8570 So far I have: -Removed and reseated the graphics card, RAM and other PCI cards. -Removed battery and let it sit unplugged over night. -Performed PMU reset. (once) At this point I have come to believe the power supply needs to be replaced. it is model: 614-0224 (360w). After looking online they are stupidly expensive, from $180 to over $500 each. I will be ordering a new MB (PRAM?) battery (Saft 3.6v LS14250C) and replacing that as well. Questions: - Have I missed anything here? Is there any other explanation or method of troubleshooting I should try? - Is there any cheaper source for the power supplies? Why are they so absurdly expensive? Does anyone here want to give me a sweetheart deal on one? - Can anyone recommend a source for the LS14250C battery locally in Manhattan? Radioshack has it as an online only item and wants $15 for it.