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Redsand187
Dec 16, 2010, 02:15 AM
2.5 quad G5 will not boot. It will either boot to the gray screen, with the apple logo and the turning timer, or sometimes it will just go straight to a blue screen. This computer started fine, except it had infrequent kernel panics, 6 months ago when put in storage. Now when pulled out and attempted to use again this is happening. I was told that a bad processor may be the cause of the kernel panics. However, the machine never refused to boot when in operation before storage.

Also it looks as if LED #2 and #7 are lit up.

I'm kind of at a loss. It will not boot from the install disk or in in safe-mode. The PRAM has been reset, as has the PMU. No visible signs of coolant leaks.

Any tips, or ideas would be greatly appreciated at this point. :(



VanneDC
Dec 16, 2010, 03:02 AM
unplug asap...

remove the cpu cover (search for how to) and inspect for leakage/corrosion.....

dont re-plug it it as it could be hazzadous to your health if the psu is getting slightly damp.

if you cant do that yourself, take it to someone who can... dont stuff around with mains power, you can get a freakingly nasty shock..

OrangeSVTguy
Dec 16, 2010, 06:06 PM
Click on the Apple in the left hand side and click about this Mac. How many processors does it say?

Nugget
Dec 16, 2010, 06:15 PM
Click on the Apple in the left hand side and click about this Mac.

That's sort of hard to do on a machine that won't boot.

666sheep
Dec 20, 2010, 11:50 AM
Also it looks as if LED #2 and #7 are lit up.


See attachment. Remove all RAM except 2 sticks (test few pairs to be sure). If it won't help, it seems that CPU (or both) is gone...
It could be caused by leak. You may not see it if it's small. Remove CPUs and check pump(s), gaskets and all connections of hoses.
If you need service manual for your G5, PM me your email adress.

Redsand187
Jan 5, 2011, 12:12 AM
Okay, I started fooling around with the machine again today. I doubt it's likely, but could a bad battery cause issues like this? I have checked everything out there is no signs of leaks anywhere.

My main issue is how do I know if it's the processors or the logic board? I wouldn't mind possibly doing one or the other, but not both. If I can source affordable used parts, that is.

chrismacguy
Jan 8, 2011, 05:49 AM
Okay, I started fooling around with the machine again today. I doubt it's likely, but could a bad battery cause issues like this? I have checked everything out there is no signs of leaks anywhere.

My main issue is how do I know if it's the processors or the logic board? I wouldn't mind possibly doing one or the other, but not both. If I can source affordable used parts, that is.

You could try getting the Apple Hardware Test for your model (May be on your install disks) if you can get the machine to powerup at all, or you could try replacing components (Although this can cause fan havoc if you dont have the Thermal Calibration Disc) - other than that Im not sure how you can see which it is.

666sheep
Jan 10, 2011, 01:05 PM
I have checked everything out there is no signs of leaks anywhere.


Did you remove CPUs cover and CPUs with LCS? Big leak can be noticed without removing them but you won't see small one this way.

OrangeSVTguy
Jan 10, 2011, 08:24 PM
That's sort of hard to do on a machine that won't boot.

Yeah good point. I kinda misread the OP :o

Do you have the tools to remove the processor/LCS assembly? There could be a small leak where the CPU meets the heatsink as there is a rubber gasket that sometimes causes slow leaks. This can short out the CPU.

A bad CPU or LCS pump could be the cause. The water blocks can also be clogged reducing the water flow and causing the CPUs to overheat.