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Help: Issues with PowerMac G5 Quad-core

PowerMac G4 MDD said:
But isn't it odd that these lights only come on once a calibration test is initiated and then freezes? I suppose it may be overheating, considering it runs at its normal temperature a PMG5 SHOULD run at... although with the fans blasting. Hopefully I can find a good tutorial on flushing it. I have some thermal paste too. What do I use for coolant?
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There are a couple of different coolants that you can use. I know Arctic Silver makes some that is safe for the LCS. That being said, if it does not appear to be leaking then leave it alone. Also, if you do decide to add coolant, remove all of the old coolant first.

Try using your ASD disk to run a full hardware test. It may take a while, but will be very lucrative in knowledge if there is something blatantly wrong with the system.
 
Altemose said:
There are a couple of different coolants that you can use. I know Arctic Silver makes some that is safe for the LCS. That being said, if it does not appear to be leaking then leave it alone. Also, if you do decide to add coolant, remove all of the old coolant first.

Try using your ASD disk to run a full hardware test. It may take a while, but will be very lucrative in knowledge if there is something blatantly wrong with the system.
Click to expand...

The tests fail. I tried only selecting like 4 items to be tested, which happen to have been the CPUs, and the test finished and came back positive. I COULD maybe sit there and test four at a time, separately... but man, that would take forever. The whole program just freezes after a while, even if I don't select a test or calibration. It's as if it stresses the system out at a certain point.
 
PowerMac G4 MDD said:
The tests fail. I tried only selecting like 4 items to be tested, which happen to have been the CPUs, and the test finished and came back positive. I COULD maybe sit there and test four at a time, separately... but man, that would take forever. The whole program just freezes after a while, even if I don't select a test or calibration. It's as if it stresses the system out at a certain point.
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This does not surprise me that the CPU is throwing the error. Try to reseat them.
 
Altemose said:
Fully remove both the LCS assembly and the CPUs. Clean the old paste and reapply new paste. It is important to use special care when handling the delicate CPUs.
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just out of a curiosity, how do you remove the processors or the heat sinks from a G5, not that I would want to. Also, if I wanted to, couldn't I remove the heat sinks without the processors to clean out the dust?
 
Gamer9430 said:
just out of a curiosity, how do you remove the processors or the heat sinks from a G5, not that I would want to. Also, if I wanted to, couldn't I remove the heat sinks without the processors to clean out the dust?
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See my previous post with a link to the G5 service manual. It will tell you how to take it apart. The processor is on a daughter board that is attached to the heatsink, it is all one assembly. Same thing for the Quad, when you pull out the LCS the CPUs are attached. Once you get the assembly out you can then remove the daughter cards from the heatsink.
 
Altemose said:
Fully remove both the LCS assembly and the CPUs. Clean the old paste and reapply new paste. It is important to use special care when handling the delicate CPUs.
Click to expand...

Are the CPUs apart of the LCS or do they detach? (I am assuming any thermal paste will work. I have a tube of it somewhere)

This will probably be my last resort, as I have run out of other ideas. If this ends up not working, maybe I will part this machine out. But I will still try and see if I can re-seat and re-paste the processors.

I'll update the thread on what happens; I may perform this task during Thanksgiving break.
 
PowerMac G4 MDD said:
Are the CPUs apart of the LCS or do they detach? (I am assuming any thermal paste will work. I have a tube of it somewhere)

This will probably be my last resort, as I have run out of other ideas. If this ends up not working, maybe I will part this machine out. But I will still try and see if I can re-seat and re-paste the processors.

I'll update the thread on what happens; I may perform this task during Thanksgiving break.
Click to expand...

The processors are on daughter cards attached LCS. It's all one assembly so when you pull off the LCS you'll find the processors attached. Once you get it out you have to remove some screws to separate the daughter cards from the LCS. Back to the diagnostic LED, did you figure out what numbers were lit?
 
noodle654 said:
The processors are on daughter cards attached LCS. It's all one assembly so when you pull off the LCS you'll find the processors attached. Once you get it out you have to remove some screws to separate the daughter cards from the LCS. Back to the diagnostic LED, did you figure out what numbers were lit?
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Okay, thanks. And I need to check what lights were on. All I know, as of now, is that there was one diagnostic LED among the RAM slots, and then one right below that. The second one (below the RAM slots) would come on once ASD froze, and the first one would come on once booted into ASD.
 
PowerMac G4 MDD said:
Okay, thanks. And I need to check what lights were on. All I know, as of now, is that there was one diagnostic LED among the RAM slots, and then one right below that. The second one (below the RAM slots) would come on once ASD froze, and the first one would come on once booted into ASD.
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Take a picture of them and post it
 
noodle654 said:
Take a picture of them and post it
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Alright, I will post a picture when I work on it. I am going to work on it during Thanksgiving break. I also made a video that I posted here, which shows the lights and when they come on.
 
noodle654 said:
Take a picture of them and post it
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Further testing on the computer's fan temps showed that it went up to 200F, after vigorous testing... but the air blowing out of the exhaust vents was cool and it suddenly jumped down 30 degrees, etc. I am pretty sure this thing isn't really running this hot, unless the LCS is spazzing. I am planning on reseating the processors tomorrow. But could this be some permanent fan sensor issue? I hope reseating the CPUs works and that this isn't a problem with the sensors.

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Altemose said:
Fully remove both the LCS assembly and the CPUs. Clean the old paste and reapply new paste. It is important to use special care when handling the delicate CPUs.
Click to expand...

During vigorous stress testing, iStat claimed that the computer's main temperature got up to 200F, but then it jumped around, sometimes 30 degrees at a time... and on top of that, but air coming out of the exhaust vents is cool. This seems like the sensors are lying to me. I'll still reseat the CPUs soon, as a last resort, but I hope there isn't some issue with the sensors.
 
PowerMac G4 MDD said:
Further testing on the computer's fan temps showed that it went up to 200F, after vigorous testing... but the air blowing out of the exhaust vents was cool and it suddenly jumped down 30 degrees, etc. I am pretty sure this thing isn't really running this hot, unless the LCS is spazzing. I am planning on reseating the processors tomorrow. But could this be some permanent fan sensor issue? I hope reseating the CPUs works and that this isn't a problem with the sensors.

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During vigorous stress testing, iStat claimed that the computer's main temperature got up to 200F, but then it jumped around, sometimes 30 degrees at a time... and on top of that, but air coming out of the exhaust vents is cool. This seems like the sensors are lying to me. I'll still reseat the CPUs soon, as a last resort, but I hope there isn't some issue with the sensors.
Click to expand...

It is possible that this is caused by a faulty sensor.
 
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