This will be a brief coda to a couple of recent posts in which I related how I finally solved an ever-worsening (OS changes?) problem of overheating on my first generation MacBook Pro. See “What a Relief! MacBook Pro Overheating Problem Cured—Really” and “Can’t Boil Water With Vista on My MacBook Pro Anymore” for the details. The solution turned out to be undervolting—setting cpu operating voltages at values (determined by experiment) below the overly conservative ones set at the factory. A great little piece of software called CoolBook enables one to do that on the Mac. A similar program (RMclock) is available for Windows.
I can report that I have encountered neither high temperatures nor computer instability since adjusting voltages lower with CoolBook. After a couple of weeks of stress-free lower temperatures, I realized that the previously necessary evil of the constant droning of the MacBook Pro’s cooling fans was no longer necessary. In my earlier efforts to control temperature I had installed a System Preferences utility called Fan Control. This allowed me to set the minimum temperature at which the fan speed would start ramping up and the rate at which it would increase with temperature. This was not a solution for sustained operation at the highest default voltage used when the cpu was running at maximum speed, but I think it did keep things cooler than what Apple’s normal fan speed algorithm did.
It may seem funny that Apple would have such high operating voltages coupled with such puny fan cooling; but I think we have reason to believe that Steve Jobs hates fan noise (I’m with you there, Steve), perhaps beyond reason. I remember buying a third-party fan that sat on top of my first Mac, the mighty one-megabyte-RAM Macintosh Plus. Word was that it was needed to prevent premature death of the convectively cooled Mac. I can imagine Steve telling the engineers to get rid of that fan noise on the MacBook Pro, or else.
The fans on my machine, even though one of them was relatively new, having been replaced under AppleCare when my original hard drive croaked (Fatal But Survivable: A Hard Drive Transplant Story), seemed to have gotten noisier over time, from overuse I suppose, so they were annoying me more. Why not get rid of Fan Control? Removing it from the System Preferences Panel wasn’t hard (Ctrl-click and make selection), but this merely put the fan speed versus temperature profile out of my control, while leaving the last one set by Fan Control in effect. I saw one unfortunate on MacUpdate warning people not to install Fan Control because it permanently changes the fan settings. This is fortunately not true, but the folks that make Fan Control should probably do a better job of letting people know how to completely uninstall it. Here is the rest of the procedure: remove the following files and folders (both on your start disk)— /Library/StartupItems/FanControlDaemon and /Library/PreferencePanes/Fan Control.prefPane.
In order to have a way of monitoring temperature and fan speed I went back to running smcFanControl, a program that only allows one to set the minimum fan speed. I used it to set the minimum speed back to 1000 rpm, down from the Fan Control minimum of 1600 rpm I’d been enduring. This is really quiet!
Having smcControl running enables me to step in to raise the fan speed if necessary. Shades of the past: yesterday I was reinstalling the iPhone SDK as part of a long battle (probably not to be related here) to be able to test my in-development iPhone app on an iPod Touch, when I noticed the smcFanControl temperature reading said 90° C, while the fans were still whirring away at less than 2000 rpm. I used smcFanControl to raise the minimum speed much higher manually, which had the desired result. When that taxing installation procedure was over, I set the fan speed back to 1000 rpm.
Now that I finally have what I thought I was getting when I bought the MacBook Pro, this should be the last I’ll have to say on the subject of temperature control and fan noise. Peace.