My only concern with using a piece of copper with thermal paste on the sides is that the thermal conductivity of copper may not be the same as the original thermal pad. I would assume that it could work, but I would do my best to try and replace the pad with a similar one.

A lot of time, there will be people selling pre-cut slices of thermal pad on ebay.

I have also purchased thermal pads from Digi-Key.

You should be able to read the processor temperature on the desktop. If you do decide to try and use a copper spacer, then be sure to check the temperature and make sure that it is within operating limits.

Good luck and let us know how it works out.

Ok. Thanks for the answers. I tried the copper alternative and it worked! The first thing was: made a clay mold to know the proper thickness of the gap; then I got a piece of copper (wire conductor with 4 milimeter in diameter), cut a piece 2 centimeter long and start to smashing it until got about the right thickness... Then I cut the piece so I got a piece of (1 x 1.5) square centimeter and I did the first presentation into the space to be filled; From here on out it was a matter of polishing (with a bench grinder) the piece until achieve the proper fit. Put very thin layer of artic silver 5 on chipset, heatsink, and the both sides of the copper piece, joined and then separated them to check de paste distribution and the paste excess areas, with a card smoothed the past and joined again; I made sure about the firmness of the piece and turn on the laptop. After 20 minutes of operation (playing DVD movie and watching manga from internet) check Everest panel and it gave me 40ºC for processor, 52ºC for motherboard and 57ºC for chipset; then measured temperatures with a thermocouple and the chipset gave me 42ºC on the body of the chip and 48ºC on the top of the chip (very near to the black area where the piece of copper makes contact); for processor it wasn't possible measure with thermocouple 'cause the heatsink completely covers the processor... until this moment the fan was switched on only twice at a slow speed not like before: at top speed.

So the conclusion is: the piece of copper works but only if you can fit it properly to fill accurately the gap between the chip and the heatsink.

Thermal paste

Liked Juan's solution but being lazy, figured it was too much trouble. A penny seemed to be just the right thickness so researched the copper content of pennies in different years. Grabbed one from the 70s which was in the 97 percent range, and used a generous amount of thermal paste to fill in the gaps on both sides of the penny.

So far so good. Can watch movies without the fan blasting or the machine shutting down.

I have a Compaq Presario CQ56.

The computer had worked fine for the last year. Then it got slower and slower, and finally started freezing at random times. It actually got to the point where it was not reliable enough to use.

I took it completely apart to get to the fan. I can't believe I had to take the mother board out of this computer to get to the fan!.

I had to remove the heat sink/heat pipe to get to the screws for the fan enclosure. I removed this huge dust bunny from the fan vent. It was so thick it was like a felt pad.

I cleaned up the heat sink/heat pipe, CPU, and GPU discarding the GPU thermal pad (mistake). I used a silicone based heat sink compound to dope up the GPU and CPU.

After putting the computer back together it ran wonderfully. The fan was much quieter and did not run all the time at full speed.

I was so happy until I tried to play Angry Birds Seasons Demo.

I would get about two minutes of play then the graphics would break up, lines would be across the screen and the computer was frozen.

I then realized my mistake. When working with crappy laptops, with crappy cooling systems, if you remove a thermal pad, you replace it with another thermal pad.

I did not have another thermal pad and getting to the computer store is a pain without a car.

I tried the penny hack and it did not work. It did give me about seven minutes in angry birds before freezing instead of two.

So I guess I will have to wait until I can get to the computer store to buy the thermal pad before I will have a working computer.

At this point I have taken the computer completely apart and re assembled six times.

If that does not work I guess I will have to fork out some dough (pain considering I am unemployed) and replace the mother board and processor. It is just a single Celeron but the mother board will take a dual core Pentium.