Hey guys. I have a problem with my power mac g5. There is no boot chime and no video output. When i press the power button, the light turns on and stays on, it doesn't flash. The fans spin up , the hard drive also spins up. It is a dual 2.7 ghz. It also has 2x1 gb ddr 400 mhz ram. The gpu is a nvidia 5200. Have any of you had this problem?
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Power mac g5 not booting
- Thread starter peterto11
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The PRAM battery could be flat, the some of the ram could be bad, the gpu might need to be reseated, those systems can be a little finicky, and that's not getting into the matter of the aging watercooling in there. I'd take off some of those shrouds just to make sure there aren't any leaks.
Oh god I thought only the quad models have water cooling.
I am going to check it tomorrow I really hope it hasn't leaked. Thank you very much.
Has anyone ever been successful in using the diagnostic LEDs to actually diagnose a problem? I can't recall a single time when someone has posted about a G5 or Mac Pro failing to boot and the LED diagnostic lights were helpful in diagnosing the problem (but then maybe if they helped we wouldn't see the posts).
Yeah. Noticing the diagnostic LEDs was how I found out my Quad's LCS was cooked.
They aren't that helpful beyond identifying either a thermal or power issue, though-- they're pretty much limited to just that.
They are also only present on A1117 (Late '05) models. If your G5 is A1047 (Early '05 and older), good luck I guess?
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Hey guys, thank you for helping i am new to mac collecting and repairing them is difficult for me. Sadly the water cooling has leaked .One of the cpu boards is fine but the other one has some corrosion on it, which i am cleaning now. My watercooling unit has a single delphi pump. I drained it. Can i fix the watercooler , and put new hoses and glycol in it or do i have to search for an air cooler?
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Here is the cleaned up cpu board.. I think this will power up. Sadly there are no air coolers in my area I can buy for this mac. So i would have to restore the cooler with new hoses. Can I test if the cpus working without a cooler some way? How can i run the pump without the computer? What diameter tubes do i need, are they special for watercooling? After many hours of research here are the best guides i found for the single pump delphi cooler i am going to rebuild the water cooling. liquid cooling rebuild video :: Liquid cooling rebuild and pump maintenance
:: xlr mac guide to overhaul liquid cooler.
:: xlr mac guide to overhaul liquid cooler.
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@peterto11 What did you use to clean the corrosion? I have used baking soda and a toothbrush to clear corrosion off boards that I've worked on. It neutralizes the acidic nature of the corrosion and tends to do a fairly good job cleaning the parts.
Just ethyl alcohol and a soft paint brush because i didn't have a spare toothbrush. I just put alcohol on the board waited 15 minutes, and brushed about 10 minutes and most of it fell of. I needed a thin knife for some very hard bits that stuck to the chip's legs but i also got that off.