Keep your Mac cool this summer

Sure, your new black MacBook is cool, but is it really cool? The hot summer weather this week got me thinking about one of a computer's biggest enemies: heat.

As computer processors have gotten faster, they've also dramatically increased their heat output, making that MacBook more hot than cool. In fact, Apple no longer uses the term "laptop" when describing its portable line, because the new Intel-powered Macs can get too hot to rest on your lap for an extended period.

Now that summer is upon us, here are some ways to keep your Macs cool.

Keeping portables cool. The new MacBook and MacBook Pro models aren't the first laptops with heat issues. My first PowerBook G4 Titanium packed quite a bit of heat, so I purchased a $30 Road Tools Podium CoolPad (www.roadtools.com), a laptop stand with plastic spacers that lift the computer up to allow airflow under the case. A smaller $20 traveler version is also available if you want something more portable. The added airflow does help to cool the computer; my PowerBook's fan doesn't kick on as often when I'm using the CoolPad.

Speaking of airflow, don't leave your portable running for a long time on a soft surface such as a blanket or pillow, as the fabric can block the side vents that circulate air.

When I'm using my PowerBook on the couch, I set it on a flat surface so I don't burn my legs. You can use a coffee table book or magazine, but a few years ago I received a $48 Levenger Laplander lap desk (www.levenger.com) as a gift. It's nothing fancy, just an ergonomic piece of wood with padding attached to the bottom with Velcro, but it provides a great, comfortable work surface. You could no doubt make your own with some light wood and the right tools, or do a Web search for "lapdesk" and pick from variations sold by several companies.

Some heat issues go beyond just normal usage. Some new MacBooks recently accidentally shipped with a strip of protective plastic covering the vent near the screen hinge; if the fan on your MacBook is running most of the time, check that this plastic isn't present.

Fan club. When your computer heats up, it compensates by revving up its internal fan or fans. (Alas, all Macs now include at least one fan, unlike that brief quiet period when you could buy a fanless iMac or the G4 Cube.) Thankfully, today's Macs include internal fans that are quieter than the "wind-tunnel" models (and many PCs). If your desktop Mac's fans are particularly noisy, you might consider replacing them, as my TidBITS colleague Geoff Duncan did with his aging Power Mac G4 (see his article about the experience at db.tidbits.com/getbits.acgi?tbart=08180).

Also, make sure your computer's firmware is up to date. Last week, Apple released a firmware update for the 17-inch MacBook Pro that adjusts the fan behavior (you can find firmware updates at www.apple.com/support/downloads/).

You'll find that the internal fan behavior can help you troubleshoot problems, too. When the fans work faster, that can often be an indication that some application might have gotten unhinged and is gobbling your processor cycles. Annoying Flash-based ads on Web pages tend to spike my processors, for example.

If the fans are active without an apparent good reason, launch the Activity Monitor utility (found in the Utilities folder within your Applications folder). Click the CPU tab at the bottom of the screen, and then click the % CPU column to sort the list of running programs and processes according to which is demanding most of the system. If an application is using more than about 40 to 50 percent and it's not actively working on something (such as rendering video or other processor-intensive task), quit that application and see if the fans kick down.

I've also installed the free Temperature Monitor utility (www.bresink.com/osx/TemperatureMonitor.html) and its associated Dashboard widget, which tells me the temperature of my processors. You can find other monitoring widgets at www.apple.com/downloads/dashboard/.

And finally, if you're just trying to deal with the heat outside or in a stuffy office, your computer can help you stay cool. I bought a $10 Kensington FlyFan for my mother-in-law in Los Angeles. It's a small fan with soft nylon blades that connects to your computer's USB port for its power. The neck/cable is flexible, so you can position the fan to cool you off instead of using a big desktop fan.

Jeff Carlson and Glenn Fleishman write the Practical Mac column for Personal Technology and about technology in general for The Seattle Times and other publications. Send questions to carlsoncolumn@mac.com.

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