Too Hot To Hold

I bought my Dell Inspiron B130 laptop two years ago and I have enjoyed it greatly. The extra-wide screen is very handy for working with lots of open windows, and it has performed very well. I replaced the battery after about a year and a half, which seems to be normal for these models.

Recently, I noticed that the laptop was getting uncomfortably hot on my left leg. The upper left corner of the base has always been a hot spot, but this was beyond normal. On closer inspection I saw that the fan was also running continuously. So I decided to do a bit of investigation.

The bottom of the B130 has several access panels held in place by one or more screws. In this view, the hinge edge of the laptop is at the bottom of the photo. The access panel below the fan and to the left of the battery covers the hot spot, so I started there.

I unfastened the one screw holding the panel in place. The screw is a captive type, so it won’t fall out of the panel. The panel lifts up slightly as the screw is turned counter-clockwise. Just lift it up and slide it out. Once the panel was removed, the problem was obvious. In between the fan and the copper heat sink was what appeared to be a layer of felt. It was actually accumulated lint.

Clean It Out

Once I recognized the problem, the solution was easy. It’s really the same as cleaning the condenser coils on your refrigerator. To clean out the lint, unfasten the four screws holding the heat sink down (horizontal arrows in the photo above). These are also captive screws, so don’t worry about them falling out. With all four screws unfastened, lift out the heat sink using the bar-coded, white strap. Avoid touching the bottom of the heat sink.

As a point of interest, the bottom of the heat sink contains a dark grey square. In the middle of it is a rectangular mark caused by the matching rectangular feature on the green structure still in the computer. I presume the green device is the processor. The rectangle is probably a metallic material that conducts heat very well. The heat sink is made of copper, which is also an excellent heat conductor. When the fan blows air over the copper fins, excess heat is transferred from the processor, to the copper, to the air and then out of the PC.

In this photo, the channels of the heat sink are quite visible. They are so small, that it is easy to understand how they can be blocked by dust. Once the heat sink was out, the collection of lint was easy to remove. I also used an old toothbrush to gently clean out the ends of the channels that had been blocked. Blowing through them also helped. In the end, I used a small plastic cable tie to remove the last bits of dust. A small pipe cleaner would have been a better tool.

Put everything back together in the reverse order. Note that a number is stamped into the thick, copper base of the heat sink, next to each screw. They are numbered 1 through 4. Carefully re-insert the heat sink, and then seat each screw. I apply light downward pressure and turn the screw backwards until I hear or feel it click. Then I turn each one a quarter turn to just engage the threads. Starting with number 1, I tightened that screw fully, then moved to number 2, which is diagonally across the heat sink. Continue in order with screws 3 and 4.

With all the dust removed, the heat sink re-installed, and the access panel closed up, I was done. I am glad I caught this when I did. I’m not an expert on PCs, but I can easily imagine the processor shutting down from getting too hot. Cleaning just makes sense, and I plan to do this annually as long as I am using this computer. Although I don’t know for sure, I suspect this cleaning procedure would work on many other laptop models besides the Dell B130.

Ray: Thanks for the detailed posting. I finally fixed the overheating of my Dell Inspiron B130 and it hasn't shutdown after being on for the past 12 hrs. The heating after this cleaning has come down drastically and its convenient to use the laptop now without having to worry about when it might shutdown. Awesome.. Cheers. Cheers.