My original post, locked by this forum. Display problem related

Question

Hi G5 Gurus,
The display problem first, we all know when screen savers display, a click on the mouse will bring you back to the active desktop, this was how it worked., but now, sometimes a click cause the G5 to sleep!
As for the sleep, I dare not to put it to sleep these days, because I am afriad it may cause a fire by over heating. Sometmes, actually four times in the past few months, my G5 could wake up by itself, followed by a extrem high speed running of the cooling fan, it sounded like a hair dryer running in the same room. Sometimes the sreen could light up, just like real wake up, sometimes, it was black. No clicks the mouse or keyboeard could bring it back to normal, I had to press and hold the power button to turn it off.
This crazy problem happened for the first time last summer, a dead hard disk was the cost. Apple replaced it, but failed to detect the cooling or power or display problem. I was given one month extended free service, but right after its end, the problem was back and happened even more often.
Please let me know if any of you had the same problem and please advise what to do.
100s Gs of thanks.
Songyan
iMac G5 Mac OS X (10.4.8)
la teller
Posts: 1
From: Los Angeles
Registered: Jan 10, 2007
Re: What's the problem? Display? Power supply? Cooling? My G5's gone mad
Posted: Jan 10, 2007 2:21 PM in response to: Bad luck G5
I have the EXACT same problem. In fact, I could not have described it better myself. What gives? I brought it in to the "genius" bar and they repolaced the power supply free of charge but the problem is still there. I noticed they ordered a new logic board but did not end up replacing it after all. Did you have yours replaced and did it work? Is this a known issue?
imac G5 17 inch Mac OS X (10.3.9)
Bad luck G5
Posts: 8
From: UK
Registered: Jan 10, 2007
Re: What's the problem? Display? Power supply? Cooling? My G5's gone mad
Posted: Jan 11, 2007 1:20 PM in response to: la teller
Hi La teller,
Thank you for your reply. The 'genius' here in London only replace the dead hard disk, which I belive was a victim of this problem. I was told they couldn't find anything wrong with the power supply or the cooling system.
Now at lest I know I am not the only bad luck guy. Let's wait and see if others are having the same problem. I am not sure if this is a known issue to Apple, even if it is, it may take years before they can offer a recall or free repaire. I noticed that some G5s have already been suffering from power problems and a free repaire was offered.
Thank you again and hope Apple can take our concerns into their consideration soon.
Songyan
iMac G5 Mac OS X (10.4.8)
stopha6
Posts: 1
From: US
Registered: Jan 12, 2007
Re: What's the problem? Display? Power supply? Cooling? My G5's gone mad
Posted: Jan 12, 2007 7:43 AM in response to: Bad luck G5
Hello,
I'm also having this problem (fan running, won't come out of sleep), just spoke with an apple care rep. He confirmed my suspition that it was software, not hardware as I have just had the logic board and power supply replaced.
His suggestions were to:
1. Run disk repair from the startup CD
try running OS X from a firewire drive and see if the same behavior happens or
perform and archive and install.
When the fan starts to run like that it means the OS is not communicating with the hardware properly. The OS could be somewhat corrupt if you were having hardware issues beforehand, hence the need for a reinstall. I will be performing an archive and install after the disk repair, I'll let you know if it fixes the problem!
iMac G5 Mac OS X (10.4.8)
Bad luck G5
Posts: 8
From: UK
Registered: Jan 10, 2007
Re: What's the problem? Display? Power supply? Cooling? My G5's gone mad
Posted: Jan 14, 2007 12:52 PM in response to: stopha6
Hi Stopha6,
Thank you for your message. I never imagined it could be a software issue, cos it looked so hardware.
Please keep me updated with your progress.
By the way, as I said in my old posts, a hard disk went dead when this happened for the very first time, how do you read this?
Thank you.
Songyan
iMac G5 Mac OS X (10.4.8)
Bad luck G5
Posts: 8
From: UK
Registered: Jan 10, 2007
Re: What's the problem? Display? Power supply? Cooling? My G5's gone mad
Posted: Jan 15, 2007 6:58 AM in response to: stopha6
Hi Stopha6,
After reading your reply again, I realized that the system had already been reinstalled. As I said when it happened for the first time, the hard disk died with it, which was replaced, of course with a new OS X, but the same problem is still happening. May this suggest that it is not just a software problem? Thank you. Songyan
iMac G5 Mac OS X (10.4.8)
AG-Nate
Posts: 5
From: Pismo Beach,CA
Registered: Aug 26, 2006
Re: What's the problem? Display? Power supply? Cooling? My G5's gone mad
Posted: Jan 14, 2007 3:38 PM in response to: Bad luck G5
The Fans going at full is only because you have an application that is using a lot of cpu power and therefore causing the imac to heat up so it turns the fans on. The screen-saver and sleep problem you describe sounds like something that may just happen on accident. But this sounds mostly like a software problem. Try making sure to always quit all non-apple products and see if anything changes.
eMac, iMacG5 Mac OS X (10.4.7) 800mhz 1gig ram, 2ghz 2gigs of ram
Bad luck G5
Posts: 8
From: UK
Registered: Jan 10, 2007
Re: What's the problem? Display? Power supply? Cooling? My G5's gone mad
Posted: Jan 15, 2007 6:50 AM in response to: AG-Nate
Thank you, Ag-Nate. I will try as you adivised but I con't think the fans were activeted my intensive CPU using. In most of the cases, the problems happened when the Mac was sleeping, when the minimum CPU were being used.
iMac G5 Mac OS X (10.4.8)
Timothy Klein
Posts: 15
From: Denver, CO, USA
Registered: Dec 6, 2004
Re: What's the problem? Display? Power supply? Cooling? My G5's gone mad
Posted: Jan 31, 2007 1:02 PM in response to: AG-Nate
"The Fans going at full is only because you have an application that is using a lot of cpu power and therefore causing the imac to heat up so it turns the fans on."
That's only partly right. A hard-working process will make the fans run at high speed, of course.
But, the OS is in touch with the firmware of the iMac, telling it how to run the fans, based upon information the OS X kernel is getting about the state of the hardware.
If the firmware loses touch with the OS for some reason, and is not getting instructions on how to run the fan, it will default to running them at full blast, to be on the safe side (and this "full blast" fan mode is way louder than anything you'll generally experience during normal usage, I know from experience).
So it may not be so simple as a hard-working cpu process kicking the fans on.
iMac G5 17" 1.6 GHz Rev. A Mac OS X (10.4.8) 1 GB Ram
Kensall
Posts: 2
From: London, England
Registered: Feb 2, 2007
Re: What's the problem? Display? Power supply? Cooling? My G5's gone mad
Posted: Feb 2, 2007 9:05 AM in response to: Timothy Klein
Hi I have a 20" G5 imac it's about 18 months old and I am having the same problem, It freezes and the fan runs really loud. It's nothing to do with software as my I.T. guy has done a complete re-install. All of our admin people have imacs of differring ages and the flat panels are all OK but every one of the G5s has had a booting problem. Some fell into the recall for replacement logic boards but the one I have at home is the newest and doesn't. I'm waiting for my apple reseller to get back to me, but it looks like it's the logic board and as none of the serial numbers fall into the recall, I'm expecting a big bill. I'm really disappointed as I've been a professional apple user for over 15 years and have grown to expect a certain amount of honesty and integrity from them. Looking at all of the discussion boards and the amount of people complaining of the same problem the logic boards are defective and apple should be replacing these free of charge.
i mac G5 Mac OS X (10.4.8)
a brody
Posts: 15,170
From: Silver Spring, Maryland. Don't forget to backup your data!
Registered: Dec 23, 2000
Re: What's the problem? Display? Power supply? Cooling? My G5's gone mad
Posted: Feb 2, 2007 10:27 AM in response to: Kensall
Kensall,
Welcome to Apple Discussions!
As in the other thread I wrote:
Being from England, you may find the repair program under these pages:
http://www.apple.com/uk/support/imac/repairextensionprogram/
http://www.apple.com/uk/support/imac/powersupply/repairextension/
Check both of them as they refer to different models.
If neither of yours is under the program, please start a new topic thread so someone can help you.
http://discussions.apple.com/forum.jspa?forumID=881
First off, you'll get a wider audience who may be able to solve your problem. Secondly, responses to you won't confuse the original poster with solutions that don't apply to them. And thirdly, you'll know for certain whether or not a response applies to you.
iMac C2D 2.17/20 inch/iMac G5 1.8 1st gen/iMac G4 800 Mac OS 9 Mac OS X (10.4.8) EyeTV 200, Canon PS A530 , Epson P-R220, iSight, Airport Extreme, 5th Gen iPod

Answer 1

I am having a very similar problem. My G5 imac has already had the logic board replaced from the leaking capacitor problem. 8 mos. later the power supply was replaced under the second recall program when it failed to start up.
It had been working now for almost a year, when about 3 mos. ago I started to experience the sudden dimming effect - if the display was untouched the screen would dim about 30% similar to a laptop in energy save mode. I checked and none of these types of options were set in the pref panes. At the same time I would have the iMac go to sleep after a while from non-use, and then when I tried to wake it it would stir for a few seconds and then go right back to sleep. It took 2-3 attempts to wake it up.
Then last week, as I tried to wake it, it just shut down instead completely. I had to hold the power button down to recycle it to get it to come back to life (3 times).
Today was it - I found what I thought was a sleeping iMac, but it will not power up at all. I opened the back cover and the power supply is working, but I cannot get the board to energize, I reset the PMU, but the #2 LED won't even blink. It is completely dead.
Basically every time I used this computer I held my breath that it would not work. After 2 recalls I still only get 9 mos. out of it? Apple is really starting to show it is like the "big" computer makers, the quality is going right down the tubes.
iMac G5   Mac OS X (10.4.4)