imac temperature fan control problem

hi i have an imac i bought from a friend that i use for sound engineering with pro tools and reason. its in perfect condition except for a problem it has had since before i owned it which is that it is always overheating. i have smc fan control and it always says between 70 and 80 degrees when i turn it on and progressively gets up to about 90 before it freezes and i have to hit the power button. no part of the imac feels hot at all when this happens and it happens even if its been off for a day in a cold room. the friend i bought it from had it reformatted for me and it didn't have this problem for no more than a few days after i started using it. it also, after the temp problem became regular, wont even boot up all the way most of the time without freezing and when it freezes the loading cursor is present and i can move it. usually after i try to boot it up a couple times it will finally start fully and already be at 90 degrees but with the fans on full blast it will go down to about 80 and level out if im not doing much on it. my imac is a very important piece of equipment and its getting worse so i really need to get this fixed. there must be someone out there who has experienced this problem.

Are those temperature measurements in Celsius or Fahrenheit?

In addition to what cwa107 asked, it would help if you told us the year and model of your iMac and which version of OS X it's running.

Fahrenheit. Mac OS X 10.5.8. Not sure about the year.

tenderpile said:

Fahrenheit. Mac OS X 10.5.8. Not sure about the year.

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If your iMac temps are in Fahrenheit...those temps (70, 80, 90°F) are absolutely nothing to worry about. Think about it...if the room you are in is 80°F...then the computer will at least be 80°F (and of course higher if the room temp. is higher). Your iMac should probably have temps of 140°F or higher. Some folks with Macintosh laptops regularly report temps of 170, 180, and 190°F.

If your iMac is having "freezing" issues...it's most likely not temperature related.

- Nick

For some reason I'm doubting they're in °F.

Agree with you Brian. Do a Google about cracking the iMac and cleaning out the dust.

Your average iMac idles at about 100-120F, so 70-90F is nothing to worry about. If it's shutting don at 90 it's something else, but not heat.

BrianLachoreVPI said:

For some reason I'm doubting they're in °F.

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I was kind of thinking the same thing...70, 80, or 90°C would definitely be a different situation.

- Nick

baggss said:

Your average iMac idles at about 100-120F, so 70-90F is nothing to worry about. If it's shutting don at 90 it's something else, but not heat.

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Hey baggss (or anyone else with Intel iMac's)...what sort of temps do you get if you're watching internet videos like You-Tube?

Just curious how iMacs compare with MacBooks/MacBook Pros.

Thanks,

- Nick

SMC fan control doesn't even work with the new iMac. Mine sits there and registers 32 °F the entire time...

Go into the smcFanControl preferences and double check it is º F and not ºC which on my copy is the default setting.

pigoo3 said:

Hey baggss (or anyone else with Intel iMac's)...what sort of temps do you get if you're watching internet videos like You-Tube?

Just curious how iMacs compare with MacBooks/MacBook Pros.

Thanks,

- Nick

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If I'm watching a couple Youtube/Vimeo vids...15 minutes or so...I'm around 91 - 95F....I don't watch a lot of lengthy video...I do edit HD video and only hit 120F or so on a 3:50 minute video render...FWIW...

YouTube videos don't seem to really phase the machine at all. Maybe 125F or so.

The only time my iMac really heats up is if I'm using Handbrake for it's intended purpose, more so if I use the internal DVD drive than one of my external drives. With that I can get the CPUs up to 180F-ish. I use SMC set to Medium and try to keep it below 145F when using HB though.

baggss said:

YouTube videos don't seem to really phase the machine at all. Maybe 125F or so.

The only time my iMac really heats up is if I'm using Handbrake for it's intended purpose, more so if I use the internal DVD drive than one of my external drives. With that I can get the CPUs up to 180F-ish. I use SMC set to Medium and try to keep it below 145F when using HB though.

Click to expand...

Thanks for that. Sounds like what you and "codda" above are saying is that You-Tube videos don't tax the cpu & gpu in iMacs like it does with MacBooks & MacBook Pros...or iMacs have a better cooling system.

I guess I was trying to figure out if the OP is correctly indicating that their temps are in °F or °C. As a number of us have mentioned...70, 80, or 90°F is nothing at all to be concerned about...but 70, 80, or 90°C...could be a different situation for an iMac...especially if watching You-Tube videos on an iMac (usually a somewhat strenuous activity)...results in temps only in the 120's°F.

Thanks again,

- Nick

No question the new iMacs have a better cooling system. Maybe they're using Anti-Freeze?

Seriously, I can't get our new iMac at the Office to go above around 35 degrees Celsius. I've run games that normally would drive my MacBook crazy but don't seem to affect the iMac at all. The CPU and hard drive fans run at around a constant 1200 RPM with only a slight increase when doing some CPU or GPU intensive things.