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Britlad1989

macrumors newbie
Original poster
Sep 25, 2009
4
0
Colorado
So...basically what is going on is that after a while, depends on how hard my computer wants to run and make itself hot, it will completely shut down. . .not sleep, power off. Anyone have similar issues?:eek:
 
It's one of the newer iMac g5's (the chrome one) 20' with 2.4ghz processor...and 300g mem...i've been running istat to see what kinda temp the computer shuts down at...any where between 128-135, with my fan running around 1700rpm? any help?
 
It's one of the newer iMac g5's (the chrome one) 20' with 2.4ghz processor...and 300g mem...i've been running istat to see what kinda temp the computer shuts down at...any where between 128-135, with my fan running around 1700rpm? any help?

iMac G5 was white, not chrome.
If it's a 2.4Ghz it's an Intel for sure.

Are your temps in °C or °F?

Anyway, it should not happen.
After 20 years as mac user I have never had a machine shutdown due to overheating
 
my imac g5 als turns off when it overheats.

from cold ie been off for some time and is at room temp - it usually take around 6 hours to power off.

if i turn it on again after a while, it takes less time to power itself off.

i've traced the problem to the psu - i've removed it from the case and extended the atx power cable so the psu is running cooler.

it's stable for well over 24 hours now ie i've not seen a power off yet.

but having opened the psu, some of the caps do look suspect.

so i'm wondering if it'll last long or if i'm postponing the time when i need to buy some new caps
 
Well, a way to try stop it overheating is to download SMC Fan Control. When the computer gets hotter than you want it to put the fans on max speed. My white 2007 intel iMac's max fan speed is 3600 rpm. If yours gets up to 130c on 1700 rpm so maybe if your fans are running at 3600 rpm then your computer will stay cool. Or cool enough no to crash.

Also clean out the intake vent on the back of your iMac (just under where the stand connects with the computer) and make sure nothings blocking that or the outtake vent (a thin vent on the back top of your iMac).

Also if it's against a wall or something pull it out a bit so it has room to breathe and try avoid using it in hot places or direct sunlight.

If you do all of the following and the computer still overheats then put a normal table fan behind your iMac in a position so it blows hot air away from the computer (Do not blow it back into the computer). If the fan is on low it should be enough but if it's temp is still high then turn it up to medium or maybe even high.

Hope one of those things helps!

Good luck!:D
 
If you're relying on SMC to fix overheating shutdowns, you're just solving the symptom not the problem.

Make sure the vent isn't blocked, but aside from that, a healthy iMac is happy being hot in a hot environment.
 
Thanks for the help guys =) it is the chrome edition, not the white version of the G5, and the temperatures were in F not C...but apart from that, the only other thing I can think of that might help, is that after this complete shutdown, the top left corner (from about the middle of the sides to the corner itself) is BURNING HOT compared to the disk side. . .and even during operation, that one corner is producing a sweltering heat, hot enough to almost burn your hand =/

Any ideas what is located in that specific corner? Also when the screen is off, it looks like a pixel burst happened, almost like someone burned an image of a solar flare into the monitor, in that corner only as well...
 
ANNNDDDD one more thing! =/ sorry

But I've found that certain applications will cause it to shut down REALLY quickly, whereas others can be open for ages! For example, if i'm chatting (using the chat feature) on FACEBOOK, my computer shuts down in about 20-30 mins, but if I'm playing World of Warcraft (the biggest application on my computer) I can play that anywhere from 3-4 hours, the computer will still be running after that, not overheating, and still be fine to go back in and play for another session. WTF?! :mad:
 
The G5 iMacs were called G5s because of their processor; the white iMacs before your iMac model had power pc G5s in them.

130 f and shutdown? Geez. My G5 basically idles at 164 f and never shuts down-- only experiences slow down for stuff like typing and streaming videos.
 
take it in to a store if you can

i had a white g5 which could shut down and it was a heat issue

best thing is istat pro or something like it to monitor temp and smcfancontrol to manually change it when you need to
 
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