Is it true that iMac G5 have an over heating problem?

"is it safe to leave it in "highest""

jf,
Yes, it is safe. While some users who consistently use the "highest" setting have suggested on these boards that such use might be causing them a higher average processor temperature by a few degrees, they have otherwise reported no problem specific to that setting.

Referring to pages 14-15 and 24-25 of Apple's May 2005 iMac Developer Note, it would appear more likely that such a higher average processor temperature is not a result of the setting itself so much as the heavier use of the processor by the users' applications.

Heavy use would leave the processor with neither a more typical gradual ramp-up in temperature, nor a lull or rest period when the fans might be expected to lower the temperature to a point at which the fans could throttle back a bit. With both those moderating advantages missing from the calculation, naturally the average would be slightly higher.

In addition, some users have reported here that their iMacs actually do go to sleep when they overheat, just as they are designed to, whether or not a hardware failure is involved. A significant percentage of those not experiencing a hardware failure have also reported that lowering the ambient temp of their environment has eliminated the sleep due to overheat circumstance.

There are routine maintenance procedures that, when performed, help to moderate operating temperatures, as does the occasional removal of dust or pet hair from the insides by those who have those extreme situations.

As to your original post, where you mention - "nearly burning their house down" - and your resulting natural concern at reading such, please keep in mind that any electrical product that actually produced such catastrophic results would be quickly banned and recalled long before this point in time and number sold.

To actually find non-biased statistics as you've requested, I don't know where you'd find better than reports coming from a non-related enterprise such as Consumer Reports, Underwriters' Laboratories, Inc. or the U.S. Government's Federal Trade Commission, as well as from consumer polling organizations such as J.D. Power, etc. Sorry I don't have first hand knowledge of what's available - as a happy long time Mac user, I've never had reason to look!

Ive had the new imac model for several months now, and i have had no problems at all and i tend to work mine fairly hard. i always have at least 4 programs running at the same time for most of the day. for about 5 or 6 hrs nearly every day i will have 6 or more very big programs runing. i would not worry about it. before this one, i had the origional imac that came out in i think 2000. i ran it the exact same way. it did get hot but it was not enought to cause any damage. i would run both os 9 and panther at the same time along with 4 or 5 others and i still had no problem, even after 5 years.

myhighway, great info and +'s to you!

I have been looking for a .PDF like that on the first gen G5 iMacs and can't seem to find it. What is the general page that I can use to find developer notes like that on other models?

jf,
sorry I don't have any links, but you know they have to love publicity, so call 'em up and tell 'em you're writing a "piece" and need some info on where things stand;-)

Eric,
I just try to bookmark them when I see someone else post them - I assume they're from members who are part of the "Developer Connection" or something. Apple must not mind, as they never get deleted. There was an earlier iMac G5 one almost exactly the same wording (only adjusted for processor/bus speeds) dated August 31, 2004, I have it on my iDisk, but I somehow lost the web address:-(

And I have this
PowerMac G5 Developer Note from April 2005, but it's a different format than what I've usually seen in the past.

Don't be fooled by what you think these iMac's can or can't do. Just go to some of the more specialized boards and look at the posts of people who work these iMacs so hard they don't have the time to be bothered with running a permissions repair!! or to post on a different forum board.

Edit-
Now that I've started to read some of those other boards, I'm getting a better appreciation for the "desperate for Help" titled threads we occasionally see. And here I was, thinking they were usually newbies looking for attention. Well, I might not be using all that heavy duty stuff, but I did manage to change out my hard drive{:-)

jf,
Nothing more that I'm aware of. I imagine that would get into Apple's proprietary property, if you were able to find out exactly how the PMU communicates back and forth with the SMU, etc., etc.

As it is, I was pretty impressed with having access to that relatively simple explanation. Combined with the operating record (lucky or whatever) of the Macs I've owned, it sure gives me a lot of confidence for when I leave it running all night long in the same room in which I sleep.

JF:

First of all, no ones house burned down because of the iMacG5. There were some PSUs, that were defective and unless you lost your sense of smell completely, one could smell it before any damage to the mansion could be done or your room.
Not only did houses not burn down, no one was blown up by the G5, first or second generation. Why do you want to know the failure rate after 6-8 months? That is a strange request!! If you've been following these threads, you could get some idea-not very high. How would anyone reading everything here would be able to determine that.
I think you have received more than sufficient input to make a decision. Either buy it and get off the pot or forget about it. I don't think you would be happy with the iMac even if it were picture and tecnically perfect.
AND I WISH PEOPLE WOULD NOT FALL FOR YOUR SONG AND DANCE AND EXTEND THIS ASININE TOPIC OF YOURS.
So buy it or get out.

Hi myhighway.

You can find a listing of the Apple hardware notes at http://developer.apple.com/documentation/Hardware/hardware2.html

The pdf for the original iMac G5 is at http://developer.apple.com/documentation/Hardware/DeveloperNotes/Macintosh_CPUs-G5/iMacG5Aug04/iMacG5.pdf

Cheers

Rod

Thank You! Rod,
That's very thoughtful of you, and much appreciated. I think they make fascinating reading, even more so when you own that particular model{:-)

Exactly what I was looking for Rod! Thanks a bunch.

While I am throwing +'s around today, here's a few for you too.

Rod, I'm with you on the data, its primarily a collection of information and not necessarily statistically accurate.

Dick