Overheating your Mac Mini - No problem!
If you've been curious about what happens when you overheat your Mac Mini, don't worry. I've done your homework for you!
I was on a lengthy trip this week with the Mini. My installation is particularly tight, buried in the dash, in close proximity with the heater/AC plumbing. You can check out my worklog by clicking my signature if you want all the gory details. Suffice it to say that because of the way my Mini is installed, it's actually more likely to overheat in the winter than the summer because it can suck in hot air from the heater.
So I've always monitored this by using temp monitor lite and making sure that I keep the heater set more to the feet than the upper vents (generally a 75% feet/25% upper split). Well, I forgot to do that this time and since this is the first time I've had the heat on in the car for an extended period of time, I overheated the Mini. Here's what happens.
It took about 35 minutes and the only warning I had was a single skip in the music about 5 minutes before overheat. I thought this was odd because I've NEVER had a skip in my audio, no matter what the conditions or load on the CPU.
Five minutes later the screen went black and the Mini shut down like somebody pulled the power cord. I instantly realized I'd had the vents set to all upper and had the temperature on full.
The mini docks in my dash and is removed via a lunchpail style handle I added to it. The handle is aluminum and when I reached into the dash to pull the Mini out it was almost too hot to touch! I pulled the Mini out and felt the top, bottom, sides. It felt like I'd baked it in the oven at 190 degrees.
I set it on the seat for 15 minutes until it cooled down and re-docked it, then hit the valet switch to energize the system. After a few seconds of silence, BONG! it started without complaint. I relaunched all apps and was back online with the SMART temp reading 118 degrees. Since I've routinely run it as high as 135+ F, I just monitored it for awhile and it stablilized at around 124F. I finished the trip (another 4-1/2 hours) and returned the next day with a 6 hour run. No problems with the system at all. In fact, I'm typing this entry on the Mini right now.
Thanks to whichever engineer decided that a thermal shutdown sensor was a good idea! It worked for me. Now, I suggest you don't test it yourself!