I've had my Lenovo G555 laptop (AMD Athlon II at 2.1 GHz) for nearly two years, and recently I've been experiencing thermal shutdowns while running prolonged, CPU-intensive tasks in Debian Squeeze.

Perhaps ironically but probably totally explainable, watching Flash video is not one of these tasks. I can watch Flash-delivered content in Hulu all night, and the Lenovo is fine.

The laptop overheats and shuts down when doing two things:

• Java-heavy tasks like listening to networked, software-defined-radio sites like http://w4ax.com

• Rendering videos in OpenShot

Two things that are very CPU-intensive, indeed.

So what did I do about this? I added the GNOME Computer Temperature Monitor applet to my upper GNOME panel. I can watch the CPU temperature climb and see where the trouble spots occur.

Unfortunately this panel applet only works on my Debian Squeeze system with the stock 2.6.32 kernel. It can't find the temperature information in the 2.6.38 (from Liquorix) or 2.6.39 (from Debian Backports) kernels I've installed.

I've been contemplating buying one of those laptop fan contraptions that the computer sits on. I used to have one (and I have no idea what happened to it), and that was very successful with keeping a former laptop cool.

But before that, I figured that the laptop CPU and fan could very well be coated with enough dust to hinder the system's native cooling ability.

I unscrewed the CPU/memory door from the bottom of the laptop, then pried it up (it snaps into the motherboard at various points).

I got a can of compressed air and sprayed away as much dust as I could.

I'm rendering a video right now in OpenShot 1.4.0 under Debian Squeeze's 2.6.32 kernel, and the Lenovo is maintaining a fairly constant CPU temperature of 67 to 68 degrees Celsius.

For the moment anyway, that means success.

I will report back when I have spent more time using the laptop with the cleaned-out CPU/fan area.

Quick analysis: A dirty CPU/heatsink/fan area can hinder the ability of your computer to throw off heat and cause it to go into thermal shutdown under heavy loads. Cleaning the area with compressed air can make these problems go away.