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Anondson

Q: Power Mac G5 sleeps, then freezes and fans go overdrive.

I've browsed back a bit and noticed there are more than a few other people with this same issue.

I have a Power Mac G5 Dual 1.8. After upgrading to Leopard I noticed this happening more often, but ever now and then my Mac will go to sleep and freeze there. No keyboard action will wake it. Plus, while it is frozen asleep the fans to into overdrive. I have heard the fans kick up before while the machine is awake, but I have never heard anything like when this asleep/freeze happens. My wife likens it to a jet engine.

I recall this happening once through all iterations of Tiger. But with Leopard, it has now happened four times total.

I had done a clean install of Leopard, and I've only reinstalled a few other programs—iLife, iWork, Office 2004, CS 3, so no legacy from Tiger is hanging around in there.

Still, I have a habit of launching Activity Monitor when things behave strangely and I had noticed some strange things in Leopard that has me checking this out more often recently. I think I may have noticed some odd behavior by some programs that may be related to my Power Mac G5 intermittently freeze/revving unbelievably while asleep.

It seems that there is a greatest likelihood of the computer revving while asleep when the Real Memory allocated to the kernel_task process has climbed to roughly 300 MB. I thought it might also be a factor when other apps grabbed a massive chunk of Real Memory, so I've been alert for when Safari (for instance) climbs towards 300 MB of Real Memory as well. But no, the only one that seemed for certain to be related to this issue was kernel_task climbing to stratospheric Real Memory amounts.

Quiting apps helps get stupid programs like Safari to free up its Real Memory allocation, but I don't know of any way to get kernel_task to release its Real Memory allocation to proper levels besides restarting the entire computer.

Ever since I have noticed this apparent correlation between kernal_task and the freeze/sleep + fans issue, I restart or shutdown my Mac. And since I began shutting down my Mac when I see the Real Memory of kernel_task getting too high I have not had my Power Mac experience the freeze/sleep + fans.

I would be curious if anyone else who had noticed this freeze/sleep + fans issue has noticed if doing what I describe above helps them. I'm not sure why roughly 300MB of Real Memory seems to be a tipping point for me and I wonder if it might be a different amount for other people with Power Mac G5s and this issue. I wonder why kernel_task climbs to the heavens like a spreading wildfire grabbing more Real Memory and I wonder why Safari does it as well.

Dual 1.8 GHz G5, Mac OS X (10.5.1)

Posted on Dec 7, 2007 9:17 PM

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Q: Power Mac G5 sleeps, then freezes and fans go overdrive.

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  • by BleedingStar,

    BleedingStar BleedingStar Jul 30, 2008 11:06 PM in response to PowerPhill
    Level 1 (0 points)
    Jul 30, 2008 11:06 PM in response to PowerPhill
    Well, I have a Quad Core 2.5 G5, therefore the update isn't for me, and I do indeed have the problem. The problem is not that the computer won't wake up... the problem that everyone on this discussion is referring to is that the computer freezes randomly in mid sleep with jet like fans... that is my problem.... I have tried the Sonnet update as well, but i'm not even sure if i have a sonnet sATA or not.
  • by Samsara,

    Samsara Samsara Jul 30, 2008 11:26 PM in response to BleedingStar
    Level 4 (1,320 points)
    Jul 30, 2008 11:26 PM in response to BleedingStar
    If I'm not mistaken it would be in one of your pci/pci-e slots. You can find what, if anything, is in them by using system profiler.
    Maybe Phil will correct me on that if where I think it would be, isn't.

    Edit: Of course if you bought your mac new you would remember buying a Sonnet device for it.

    Message was edited by: Samsara
  • by BleedingStar,

    BleedingStar BleedingStar Jul 30, 2008 11:32 PM in response to Samsara
    Level 1 (0 points)
    Jul 30, 2008 11:32 PM in response to Samsara
    I definitely haven't added any Sonnet Device. All I have added since purchase would be 1 video card, 4 sticks of RAM, and some external hard drives.

    I believe Phil provided an update for a Sonnet Serial-ATA card.... I can see in my system profiler what is plugged into my Serial-ATA card, but I can't see the information for the card itself anywhere.

    My box is a Late 2005 G5, and is no longer under apple care.

    I have just done reset my SMU on my box, so I guess we will see if that does any good.
  • by Samsara,

    Samsara Samsara Jul 30, 2008 11:42 PM in response to BleedingStar
    Level 4 (1,320 points)
    Jul 30, 2008 11:42 PM in response to BleedingStar
    No, you don't have a Sonnet problem then.

    The video card... an extra one or a replacement for the AGP card that was in there?

    Don't be too sure about Applecare just yet. Use that link I gave you and put in your serial number there and see. Check the other link and see if that power supply issue applies to you. Click on" About this Mac" and click on more info. Under hardware review it tells you the serial number right there.
  • by BleedingStar,

    BleedingStar BleedingStar Jul 30, 2008 11:58 PM in response to Samsara
    Level 1 (0 points)
    Jul 30, 2008 11:58 PM in response to Samsara
    I have an extra graphics card for a 3/4 screen setup. I did check both the links that you sent over.... past coverage on apple care and I don't fall into the power supply issue.
  • by BleedingStar,

    BleedingStar BleedingStar Jul 31, 2008 12:05 AM in response to PowerPhill
    Level 1 (0 points)
    Jul 31, 2008 12:05 AM in response to PowerPhill
    I wish buddy....... i've done the update and still have the issue. It seems there are more than one culprit to this issue.
  • by Samsara,

    Samsara Samsara Jul 31, 2008 12:16 AM in response to BleedingStar
    Level 4 (1,320 points)
    Jul 31, 2008 12:16 AM in response to BleedingStar
    Darn, regarding those links...
    Well, if resetting the pmu didn't help then the only next thing I can think of is removing the additional video card entirely and see if that solves the problem. If it does at least you'll know the source. Apples PCI-whatever slots can be really buggy. I had to remove my second card just to get a few Apple apps to work, which I'm still infuriated about.

    After that I really would give Apple a call and demand that they resolve your problems. Be diplomatic but insistent. Your machine is not that old and was very, very expensive, and they "should" do right by you. Please try it at least, you may be pleasantly surprised at their reaction.
  • by BleedingStar,

    BleedingStar BleedingStar Jul 31, 2008 1:22 AM in response to Samsara
    Level 1 (0 points)
    Jul 31, 2008 1:22 AM in response to Samsara
    Thanks for the help... we'll have to see if that does anything at all.
  • by Samsara,

    Samsara Samsara Jul 31, 2008 1:31 AM in response to BleedingStar
    Level 4 (1,320 points)
    Jul 31, 2008 1:31 AM in response to BleedingStar
    Just wish I could actually have helped. Remember you can always take it to an Apple "genius" at an Apple Store for a free look over.
    I sincerely wish you the best of luck. That's a really good machine you have and I'm sure you'll get it working right again. I just don't want you having to go bankrupt for that to happen.

    Post back when you get it figured out. It would really help others.

    Take care,

    Steve
  • by BleedingStar,

    BleedingStar BleedingStar Jul 31, 2008 2:51 PM in response to Samsara
    Level 1 (0 points)
    Jul 31, 2008 2:51 PM in response to Samsara
    Seems all the attempts where in vain... still have the problem.
  • by Samsara,

    Samsara Samsara Aug 1, 2008 12:08 AM in response to BleedingStar
    Level 4 (1,320 points)
    Aug 1, 2008 12:08 AM in response to BleedingStar
    I'm sorry to hear that, Bleedingstar

    I guess by all attempts you also mean a call to Apple. You still have the option of taking it in to an Apple Store for a free lookover. I don't believe you'd have been able to do that so fast. They have tests there that are more in depth then most of us can do at home. In particular they have a calibration disk that might show and fix your problem. It's a slim chance but a real one.

    And here's one thing you might try though you probably already have:

    http://support.apple.com/kb/HT1455?viewlocale=en_US

    http://support.apple.com/kb/HT1564

    Unless others chime in with a solution, I see no recourse but taking it in for an estimate of repairs. They would probably say to replace the motherboard which is darn pricey. If you were planning to get a MacPro soon I personally wouldn't have them fix it, but if you wanted to keep it you'd have to pay. Though a pauper I would, but then I'll never be going Intel.

    Good luck
  • by BleedingStar,

    BleedingStar BleedingStar Aug 1, 2008 5:40 PM in response to Samsara
    Level 1 (0 points)
    Aug 1, 2008 5:40 PM in response to Samsara
    I actually haven't called or taken in my box yet... the issue with that is that I am on a pretty tight deadline for the next month and I can't risk not having my box for a number of days, it would put me out pretty bad right now... i might just have to disable my computer from going to sleep for the next little bit until i can get it into the store. It seems this should really just be a firmware issue.... uggg.

    I'd love to get a new mac pro sometime in the next 6 months or so, but this box has still got to be dealt with because I would probably have to sell this one to put cash towards the new box.

    Does ANYONE have anymore suggestions as to what has worked for them.... seems there are lots of people with this issue, what worked for you?
  • by deboni,

    deboni deboni Aug 6, 2008 12:19 AM in response to BleedingStar
    Level 1 (15 points)
    Aug 6, 2008 12:19 AM in response to BleedingStar
    Meanwhile the CPU of PowerMac Quad has been replaced (about 1 week ago) and I never experienced a kernel panic since. So that the kernel panics started right after the last big update from Apple was just a coincidence and was completely misleading.

    If I wouldn't have had Apple care, this would have meant the end of that PowerMac.

    But now the machine works like a charm
  • by SHS1,

    SHS1 SHS1 Aug 8, 2008 10:57 AM in response to Anondson
    Level 1 (0 points)
    Aug 8, 2008 10:57 AM in response to Anondson
    My G5 fans go crazy, it freezes and this ALWAYS happens around 4am Saturday mornings...every week... so frustrating! I called Apple and they told me to reset SMU, which I did, but to no avail.
  • by aktocs,

    aktocs aktocs Aug 8, 2008 11:04 AM in response to Cameraflyer
    Level 1 (0 points)
    Aug 8, 2008 11:04 AM in response to Cameraflyer
    Yes I did notice this, my problem began after installing the security update before last. I've been jumping through hoops since with no progress. I believe that I've now lost a processor. I too am curious, as it appears to be hardware related.
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