PowerMac G5 freezes, fan is blowing hard

The Boeing-like fans are just a security feature that prevents your processors from "melting" in case your G5 is screwed up.

That Volume header issue may just happen - btw. when running Disk Utility what about the S.M.A.R.T. status?

After 3 years your hd may have come to its end of life (often indicated by clicking noise) - might be a good idea to do a backup.

What you could also do - run AHT that comes on your original installation disks.

Is your machine one of the liquid cooled G5s?

Mine is/was; the coolant leaked and killed the processors on June 20 '08.

There are loads of similar reports on the web; Apple seems to have deleted the discussion thread on this problem from these forums...

Suggest you check your machine ASAP and look at xlr8yourmac.com for reports from other coolant leak victims.

AHT is "Apple Hardware Test". It's a small partition on that Installation Disks that delivered with your G5
Insert that grey colored Installation Disk #1 and reboot your g5

At the starting chime press alt/option on your keyboard
A grey screen with all bootable partitions will show up: One of those option should be that AHT
Run it

I can say I have the same problem with different results. I too have been noticing this is primarily happening when I out the machine to sleep. I will wake up in the morning to find the fans going full blast. I have also encountered getting a phone call from someone at home telling me my computer sounds like it's about to blow up! I put it to sleep each morning after checking my emails and heading out to work. At times the room can get get a bit warm and this may be adding to the issue. I have also read not to use any animated screen savers (which I have been) and so I may just do away with those to see what happens.

I have recently encountered more system freezes where I will have audio playing, the machine locks up with the audio sounding like a broken record repeating itself. The only way to get out of it is a hard reboot by holding the power button in. Same way I have to reboot it after I find it in the morning with the fans at full speed. I have also encountered a few kernel panics as well while in the middle of working in Photoshop or web browsing using Safari or just checking emails.

I have run the Apple Hardware Test CD both Quick and Extended Tests and get a pretty balanced result of everything is OK, or a Logic Board failure where it gives me this error code - 2STH/1/2:CPU B AD7417 AD1 - from which all I have been able to gather is something to do with a thermal sensor for one for the CPUs?

My CPU die temps are not horribly hot although I notice CPU B usually runs about 7-10º F warmer than CPU A. This is pretty constant as well no matter what task.

I have reseated all the boards, used compressed air to clean it out, cleaned the fans and radiator the best I can. I had one of the CPUs replaced less than 3 months after having bought the machine from Apple. I sure hope one of the CPUs is not going bad again as my AppleCare just expired 2 months ago.

I'd really love to know specifically what the error code I get from the AHT means. So far, I have been blessed not to see any leaks inside the case which seems to becoming a more frequent issue with my model machine.

I too am very interested to hear from others who are experiencing this issue. My S.M.A.R.T. status is good so I know my HD is fine. I have swapped out graphics cards and memory to the originals, neither of which have changed anything. Going to try reseting the SMU on the board again along. Also replacing the SRAM battery even though I know it has nothing to do with this specific issue. I just notice after forcing the machine to shut down and reboot, the date likes to come up as 1969 a lot of times.

http://www.sonnettech.com/support/downloads/computercards.html

there's an update here and it fixes it!!! Spread the word!! Spread the word!!

its under: Tempo Serial ATA PCIe/PCI-X Family Firmware Updater (Mac)

I have had this same issue for some time now.... however it has been rarely, usually only the case if the computer is left on for a long period of time in the sleep state. Thought for the last few days it has became extremely horrible. It had done it to me nearly 20 times in the past week. I have just installed the update mentions from Sonnet, and and hoping this does the trick.

How could we tell if the liquid coolant was leaking?

Not even 2 hours in to the new update and i've already had the issue come up again. Seems the update did no good.

My G5 went from doing it rarely to doing it 2-3 times daily with the 10.5 clean install on different HD. New RAM also had no effect. I installed the Sonnet firmware update and am happy to report no freezing in 2 days. Hope this solution continues to hold.

Thanks PowerPhil

its under: Tempo Serial ATA PCIe/PCI-X Family Firmware Updater (Mac)

PowerPhill,

Did you happen to see if the fix works on early G5 Powermacs(PCI only, not later PCI-X)? Thinking about getting an early G5 1.6 that is crashing more often now...
Thanking you in advance.