My iMac is Overheating

By Nicole Vulcan

You use them to cool down your own body -- now try a big fan for your iMac.
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If you have an iMac and you experience an overheating computer and to start to get worried about it, you're not alone. Overheating is a common problem, especially for Intel-based aluminum iMacs. There are a number of options to try to deal with the problem. Some involve better monitoring of the computer, while others are simply a matter of housekeeping.

Check the Dust

When it comes to solving overheating issues, it can pay to try the most low-tech solutions first. To start, check whether your iMac's vent holes are covered with dust or other debris, as buildup can have a significant effect on your computer's ability to cool itself. Look at the top of your iMac, where there's a long vent that runs the length of the machine. If it's filled with dust, use a vacuum cleaner or a dust brush to remove it. Make a regular routine of vacuuming or cleaning the exterior of your computer -- dust is bad for both external and internal parts.

External Fix

Feel the back side of your iMac when you start to notice signs that it's overheating. If it feels warm to the touch, try placing a small -- or even a large -- fan at the back of the computer. This can be a big help in cooling off the aluminum portions of your machine, which in turn could cool down its inner workings. After you've had a fan blowing on the back of it for a while, touch it again; you should feel a marked decrease in heat.

Monitoring the Problem

Your iMac is equipped with a program called "Activity Monitor" that will allow you to see all the current activities on your computer. If you're working intensely on a graphics or video program, for example, you probably don't need your Internet browser open. If you close unused programs, your iMac may cool more quickly. Simply type "Activity Monitor" into the Finder and then view the various activities you've got going at once. Close the ones that aren't needed.

Internal Fix

Another option is to download a program that allows you to control your iMac's fans to turn on at a lower speed than they're currently set to. The program, smcFanControl, lets you monitor the temperatures of your hard disk, your central processing unit and other components of your computer. If none of the other lower-tech solutions are working for you, download the program. Then open it when your iMac seems to be overheating to see the temperatures you're working with, and to adjust your fan speed and frequency.