Install a Central Processing Unit in a PC

The first step will be to shut down your computer, unplug it and remove the side panel. Be sure that you're grounded before you get in there.
Now locate the heat sink. It is usually an aluminum block with fins on the side to dissipate heat. You will probably see a fan on top of it. Follow the power cord into the motherboard, unplug it there, and release the latch holding the heat sink in place.
If you're replacing a processor in a laptop, you will follow the same basic steps. The main differences will be how to get to the motherboard and the look of the heat sink.
Pull straight up on the heat sink and underneath you will see your processor. There will be a metal bar on the side. Lift that and pull the processor straight out.
Cleaning the Heat Sink

Now for the fun stuff. We'll need to clean the old thermal paste off the heat sink before replacing it. Start by wiping off as much as you can with a clean paper towel. Next you'll want to use a q-tip dipped in rubbing alcohol. It's okay if there's a little left on there, just get it as clean as possible.
Apply the Thermal Paste to the CPU

Next we'll need to apply the thermal paste to the new CPU. Put enough on there so that it covers the entire CPU, but not so much that it will squish out the sides. Now smooth it out with a flat object. Try to get it as smooth as possible with no gaps in the thermal paste.
Installing the New Central Processing Unit

Match up the arrow on the processor with the arrow on the motherboard and close the bar. Next you'll put your heat sink right on top. Push it down firmly to make sure it gets a good seal. And re-latch it to the motherboard. The last step will be to plug the power cord back in.
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