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It is possible, but there are a few problems.

1) Unless you have a massive amount of engineering abilities, you will destroy your computer.

2) No fan in that system, so how are you going to cool an already hot processor.

3) Be careful opening that thing, because if you touch the wrong thing in there it will Kill you. Not hurt you Kill you.

4) The most you could get out of it would be maybe 50 - 100 MHZ, so why bother?

But to answer your question, yes, it is possible.
 
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