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Mac G5 freezing, fans go full speed
- Thread starter cb6293
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Could be a few things. Which G5 first off? Also, what he said:
USB booting is sorta controversial on PPC macs. Sometimes it works, sometimes it doesn't. But, we do need a bit more info. Start with answering these and we can probably begin to figure this out.
There is nothing on the hard drive. I put in the flash drive, go into open firmware and type "boot ud:,\\:tbxi" or something like that and it gives me a sector size mismatch error. If I don't go into open firmware, there is a little folder in the center of the screen that flashes from the Finder face and a question mark. Mouse and keyboard don't work in this situation. I will figure out what type of G5 it is shortly.
Flashing folder means it couldn't find a bootable OS. Do you have any OS X cds or another mac with firewire?
You might be better to try booting OSX from USB first, then at least you can check the machine out - Linux can bring it's own problems even if the boot process is fine.
Ok, update. I have researched more and I found out that when I turn it on, before it freezes, a led comes up by one of the RAM banks labelled "overtemp." Shortly after, a led labelled "checkstop" lights up, and THEN the computer freezes, and soon after, the fans go crazy. I am currently trying to get a OS Cheetah disk going, but I want to fix the freeze problem first.
EDIT: I learned that the checkstop happenes when there is a memory error, and it freezes all the system's clocks and attempts a full hardware reset, but that doesn't make sense, because I replaced all the memory.
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Overtemp is normally just as it sounds - it’s running too hot. Renew the thermal paste on the CPU(s), clear any dust from the fans and grills. Check the fans are each operating okay and if it has a Liquid Cooling System, flush, clean and renew the coolant.
There is no way in hell you are going to ever get Cheetah installed, even if you fix this freezing problem.
Like every Mac, the G5 requires a certain minimum OS. The earliest G5 requires a minimum of Jaguar 10.2.7. And your G5 is unlikely to be one of the first, so it probably needs an even higher version.
Distilled water works to refill a lcs but alotta folks use non corrosive engineered coolants like coolermaster nc-1 & the like.
Everything said thus far is spot on to figure this out. Here’s a pretty decent discussion on g5 lcs maintenance, lcs flush & fill etc.
https://discussions.apple.com/thread/3065982
Best of luck. Let us know how you get on.
Everything said thus far is spot on to figure this out. Here’s a pretty decent discussion on g5 lcs maintenance, lcs flush & fill etc.
https://discussions.apple.com/thread/3065982
Best of luck. Let us know how you get on.
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Which model G5 do you have? There’s a sticker below the clear air deflector door with the model specs and serial number.
Based on the description, it sounds like you have either a Dual Core 2.0GHz, 2.3GHz or a Quad Core 2.5GHz G5.
As @eyoungren pointed out, Cheetah is a no go. You’ll want to either use either Leopard 10.5 (Retail) or a Tiger 10.4.4 Late 2005 Power Mac G5 system restore disc. You could also use the retail Tiger 10.4.7 (PowerPC) install disc.