Macintosh users, especially Mac Pro and MacBook Pro users, are often concerned about the temperature condition of their high performance computers. Temperature Monitor 4.6 from Marcel Bresink provides not only full temperature data, but also history graphs that can be exported for research and documentation.

I have been using a wonderful utility called iStat to monitor the temperatures inside my Power Mac G5. However, it doesn't have the capability to also display temperatures on a MacBook, so I started looking for another solution. That's because, when switching to the 9600M GT GPU, the fan would come on more often than I liked, in a subjective sense, and I wanted to know more about the behavior of the computer.

I didn't take long, with the help of MacUpdate, to find Marcel Bresink's Temperature Monitor 4.6. This is just one program in a suite of brilliant tools by Mr. Bresink, a luminary in the Macintosh world. Perhaps he is best known, originally, for TinkerTool.

Temperature Overview Window

This software is no ordinary piece of work. It does everything one could possibly imagine to provide the user with every bit of information possible -- and display it beautifully. That it's free is all the more astounding.

For example, the preferences pane is more extensive than most of Apple's own commercial applications, providing every conceivable avenue for customization and monitoring. Temperatures can be in the dock, the Menu Bar, a classic window (see above) or all three.

Extensive Preferences

Alerts can be set for temperature ranges, and color coded labels can be set up for the history graphs. In the example below, I picked the two highest temperatures and selected purple and red to mark them for long term monitoring.

What I found particularly heart warming was that while the MacBook Pro, in the 9600M GT mode, would have a key GPU sensor spike under heavy use, it would immediately return to steady state. That is, in a room at 74 degrees Fahrenheit, the MacBook reached steady state and oscillations were small, jumping occasionally up and down, from a constant value.

History Over Time, Hours, Days

I presume an Apple engineer would want that to be the case, but this program was able to demonstrate without a doubt that the MacBook Pro reaches steady state and stays there. Accordingly, the capability of this software not only gives information about current temperatures, but the long term behavior of the MacBook Pro with its two different GPUs.

In addition, the program goes one step further and makes available a page of system info. (See below.) This kind of capability comes naturally from a developer who's an expert at digging into the sensors and internal information stored for each Mac about itself. In addition, S.M.A.R.T. data from the internal drive is also made easily available. It's that going the extra mile that makes the user feel that this is a professional, long term, and steady companion piece of software -- not something that's tried once then forgotten about.

System Info

The list of small things that make this program outstanding goes on and on. One can export temperature data in text or CSV format for analysis and plotting in a spreadsheet program. In the preferences, one can set up voice alerts if one of the sensors goes out of pre-defined bounds. This especially helpful if, say, the MacBook's enclosure, bottom side, gets too hot.

Because there are so many temperature sensors monitored, the preferences allow a lot of color customization. If properly configured, one can even monitor another Mac remotely.

The documentation consists of the Help menu, and that's all that's really needed. Plus, there's an on-line guide with even more details. Also in the help menu is a link to contact the author directly, and Mr. Bresink is easily accessible in my experience. Also, he communicates in perfect English, even though he's German.

Bottom Line. In the process of evaluating a program, one looks at many elements. Typically, software comes up short in one area or another, even when it's very good. Temperature Monitor 4.6 excels at everything and goes well beyond what one may have come to expect from freeware. What's more, it can even be used for research or diagnostics which makes it even more valuable, long term. Every small Mac app, free or for pay, should offer this much excellence and value.