2009 i7 Gets WAY Too Hot!!! Gaming on this is a ticking time bomb!!!

Really not that hot considering the dimensions of the iMac case.

146 F is actually 63 C which is not bad for a CPU under heavy load.

172 F is actually 77 C which is a little hot but not out of the ordinary for GPUs. Check out this for a temperature comparison of the Radeon 4850 vs other GPUs. And remember, the iMac uses a Mobility Radeon chip rather than a desktop 4850 chip that is tested on that page so your chip will run cooler.

Don't worry about the temperatures and enjoy your iMac. Apple wouldn't design a ticking time bomb. The temperatures are within specifications for each component and fans are there and will kick on when needed. I've gamed on my iMac for hours straight with no problems. Oh, and it's normal for your iMac to be very hot to the touch. It's aluminum case actually helps dissipate heat away from your computer. So in a way, the case acts like a heat sink itself.

And, as far as the 4850 only handling medium settings... The GPU was actually made in 2008, not 2009. Apple typically uses slightly older GPU components. The new iMacs use the 5600 and 5700 models of Radeon chips which I believe are a year old already. Also, Apple uses Mobility Radeon chips in their iMacs which are laptop chips. They do this to keep temperatures down and power consumption down. So those chips will be a little under powered compared to their desktop equivalents. I've been very happy with the 4850 in my iMac. It runs Mass Effect 2 and Dirt 2 like a dream. I need to turn down the anti-aliasing sometimes but it runs smooth at 1920x1080 w/ all settings set to high.

The amount of threads of people worrying over iMac heat and relating it to the case being hot to the touch is getting kinda out of hand.


My old G5 iMac basically idled at 74c, and never once broke down or crashed.

The new iMacs by far offer better cooling implementations than the previous iMacs apple released. Apple jumbo sized the heat sinks, separated the heat sinks to different sides of the computer, and put an all-aluminum case on it to further heat dissipation. The inclusion of larger fans meant that Apple could get away with lower rpms to make the computer run quieter, and still provide adequate cooling.

Gaming will make your GPU get hot, 70-80c is nothing to worry over. Both GPU and CPU alike can handle temperature in excess of 100c. The only component you should really worry over when temperature is concerned, is the HDD.

The shell is aluminum, and aluminum just so happens to conduct heat extremely well, that is by Apple's design. Do not worry over it.

As for poor performance out of the mobility 4850: it is a very good card, but if you're gaming under OSX, expect horrible gaming performance. Gaming under windows is much better (you could even overclock the mobility 4850 back to desktop standards like I do)

iMacs do run a little warmer than desktops. For a 27" iMac 63º c is not bad at all. If you have an LCD TV feel how warm that gets after 2 hours.

My Mac Pro normally hits 60º c while rendering and they genrally run cooler than iMacs.

Well, using an application like smcfancontrol or the like may just give you the peace of mind you're looking for. With smcfancontrol you're able to control exactly what rpm you want your odd, hdd, and cpu fan speeds to run at. I personally only use it because I game in windows but you can only control the fans from the mac side itself. It's definitely something to look into if you're picky about temps.