Mac Freezes and fan goes into overdrive!

I, too, own our favorite model G5 and have experienced similar problems with waking it from sleep and, when I first bought it, the infamous jet-engine ready for takeoff sound. I also used to have trouble putting it to sleep, whereby the optical drive tray would have a seizure in its place, ceasing when I moved the mouse.

Then sometime around last summer my power supply failed and I had a hefty $1K repair cost (I didn't have applecare for this machine). The Apple staff offered absolutely no insight into the cause or prevention of the problem.

I have to say, though, since having this procedure done, I have none of the problems either I have mentioned or have come up in this thread and it works like a gem--sleeps well, wakes well, fans don't go into overdrive, etc.. I think though, that the last of these problems was indeed caused by this model's unique LCS Heatsink liquid cooling technology.

Might I suggest for any of you still experiencing the problem at hand to make sure your processor speed is set on "automatic" and not "highest". This may remedy the fan/convulsion issue at least.

Hope I have been helpful!

-LSpace (Tim L)

Just to add my voice: dual 2ghz powerpc G5, nothing fancy on it (ok, a wireless logitech mouse and keyboard, some third-party RAM and a second hard drive). But it does the freeze/fast fan/hovercraft thing and has to be 'hard' restarted. It does it often, so often in fact that it has finally taught me to save as I work. It doesn't matter which app I am using, nor what the ambient temperature is.

Now I figured a while back that this might burn the house down. It's a secondary machine in a secondary house, for which reason I could not quite get the energy up to make Apple fix it. Instead I just turn it off when unattended, which is very boring.

I also knew that this was the sort of thing that would never get replicated when in the 'shop' and that it is also (how many years have I been using Macs?) the sort of thing that Apple would never admit was a frequent problem.

However, reading this thread has made me think: there's a clear pattern, Apple refuses to acknowledge it, they are selling faulty goods with no chance of repair even under Apple care. So what should we do?

I own five macs at the moment. Truth is, they are ALL dodgy in one way or another. They are all less reliable than I remember PC's being way back when. So I'm going to vote with my feet and wallet and support the underdog from now on. Vista, here I come.

As for the chances of those who stick around trying to get a resolution to the current problem?

Dream on!

t

I also have this problem (well, my G5 does). For over a year, the fans suddenly go into overdrive and a kernel panic follows forcing a restart. Always when I am away from the machine and it has gone to sleep. I also noticed the machine had slowed down considerably. Ran numerous tests but couldn't find anything wrong. Repaired permissions, etc but still happened.

I backed up my Tiger installation onto an external hard drive and did a complete wipe and clean install of Leopard, hoping this would resolve the problem. For a while the machine seemed a bit quicker but that may be wishful thinking. The fans still go ballistic every now and then when away and machine sleeping but now also occasionally start up whilst I am working, a hard drive seems to make a lot of noise from time to time and I now get kernel panics and instruction to restart immediately 3/4 times a week. I have again run the diagnostics but nothing seems wrong. The details in the report after the crash states 'ATA device failure'.

I had thought this was machine specific since I have other Macs with no such issues, running Leopard and Tiger but after searching today on ATA device failure I found this thread and it seems it is quite common. The Applecare on this machine expires end of March so I am thinking I should try and get Apple to fix it.

Has anyone had any luck resolving this issue?

same exact issue here... so many people have this problem and there don't seem to be any answers. and apple is no help. it's so discouraging... generally when it occurs (daily) i unplug the powersupply for a few minutes. it resets something and i can get it work continuously until it falls asleep again. i know i could just disable the sleep feature.. but then sometimes it doesn't even start up after being turned off. and i hate the fact that i can't depend on this (very expensive) machine to function properly.
i found this and maybe this could be of some use:

http://www.apple.com/support/powermac/powersupply/repairextension/

probably not though since apple/ applecare seems to deny the problem even exists. every time i've taken it in, it "preforms perfectly" but, of course, the second i get home, it's the same problems over again.

After talking to Applecare about this, they asked me to run the advanced hardware diagnostic test and advised that if it reported an error, I could take the machine into an Apple Store for repair but if not, to call them again as it would be a software issue which they could help me resolve.

I ran the test - according to the information on screen, it should take 15-30 mins depending on the amount of memory. With 3Gb RAM, it took one hour and 24 minutes to complete this test, with the fans running ballistic the entire time, sounding like an aircraft about to take off! That to me seems a very long time but after it completed, it reported that everything was fine and all tests were passed! So, I'll be calling Apple again tomorrow to see what they suggest.

Ahhh. What is interesting to me is that apple sometimes refuses to acknowledge there's a problem. And, of course, the first step to recovery is admitting there is one.

Problem: During sleep mode, the computer freezes and the fans begins flying. No error message is displayed either at the time, or upon doing a hard reboot. No record of the bug is in the system log. No unusual software is left running overnight, just Firefox and maybe Miro.

I have encountered this problem on a G5 dual 1.8ghz PowerPC machine, but interestingly enough, also the same problem on an old crappy G3 ibook. Here is what I've found which leads me to believe that it is not a hardware issue, but an OS issue (though of course I could be wrong).

Both my computers work fine. Absolutely fine. However, upon installing certain software (even if my machine meets all the system requirements) I will wake up in the night with my computer ready for liftoff. And, this only happens after the computer goes to sleep. Upon removing the software, my machine works fine again. (I mean, I've heard of humans having dreams where they are flying, but really!)

Software that has caused this includes: A screen-saver downloaded from the BBC "Life on Mars" website. After Effects, trial version downloaded from the Adobe site. I wish I could remember the other one, but sorry.

At any rate, this has happened to me at least three times, and the only thing I did differently was to download some new software. Once I get rid of it, whether by deleting or re-installing the OS, it's fine again.

Boy, I sure do wish Apple would take this seriously. I mean, come on, we buy these machines for the sole purpose of using software. What good are they if you can't install new things?

I feel your pain. My G5 will "freeze," then the fans start revving up high. This started last summer, when I was running Tiger. The Apple Store replaced the processors, and things were fine for a few months, then the same cycle of freeze and fans revving up. I installed Leopard, but no help. The Apple Store replaced the video card, but I still have the problem occasionally, especially during "heavy" processing jobs like burning DVDs with iDVD or even exporting Quicktime movies with Final Cut. I hardly have any software installed since my last clean install.

I disconnected all peripherals except my Logitech wireless mouse. I'm going to try that next.

And of course it has happened to me also, 2.7 DP G5. Often from sleep mode.

After reading all of this, I'm convinced that it is a hardware design flaw, that Apple's never going to cop to, especially since all of our machines are no longer in production.

I'm not suggesting you're wrong; you probably know more about this stuff than I do. But, what is the reasoning that makes you think it's hardware? Any idea which part of the hardware?

It happens too often, I guess I'll take mine in to the shop and hope for something better than what happened to all of you...
wish me luck

Just to add my two cents...
I have had my G5 for about three years. It's worked great with no problems. I just upgraded to Leopard 10.5.2 and after going through all the Software updates and installing all the newest system and iLife, I got the "Hovercraft" fan activity for the first time. It happened after it had gone into sleep mode and I could hear it revving up from the other room and went in to find it in near take-off mode. Hard shut down with a restart, and nothing again for the last 24 hours, although I have shut it down rather than let it sleep recently.

Hi!

Same here, G5 Dual 2x2.3Ghz freezes randomly and no wake up from sleep. Four months ago Apple replaced one of the processors, 700€. It seems that, with Power Save control panel set to minimum processor speed, the freezes are less often. Mac OS 10.4.11
This is a nightmare. : (

Do re-installs work as well on MACs as they do on PCs?

I know when I first got my G5 a little over 2 years ago I had my first experience of a glitch... mainly I think because I overloaded the system with installing things left and right?!?!

I re-installed and slowly added programs I needed and have never had an issue again (knock on wood). So I guess that brings me to my original question... with all these issues people have mentioned would a fresh install help or is it not worth the time?

ciao

My G5 freezes even starting up in Open Firwmare, so I think is not a software issue related. I suspect is something wrong with PMU, because if I perform a reset of the motherboard, the machine works fine for a while.

Message was edited by: Juan U.

i had similar issues
see this post http://discussions.apple.com/thread.jspa?threadID=1430861&tstart=15

i think you are right ,thinking that's a hardware design flaw.
the best thing we can do is to make a web page (similar to the page some users created for the liquid cooled machines).

this is the only way to put some pressure to apple to acknowledge the problem...
if i knew how to create a webpage,i would have already created myself