Lapping a processor is a way to lower the temperature of the processor without needing to add new and bulky hardware, or a liquid cooling system. The process involves sanding off the top layer of material on the processor and exposing the copper heat sink attached to the processor core. The layer being sanded off is mostly effective for heat transfer but primarily used to keep heat away while always providing a tarnish free surface.
Processors are produced in bulk so manufacturing defects can and will occur. While you may think your processor is flat and everything works correctly the truth is that the top is very un-flat and there are a percentage of internal transistors that in fact do not work. In the processing game everything is based on percentages. The surface of your processor is very crucial for heat transfer: the smoother the surface -> better contact to the heat sink -> better heat transfer. The end result of lapping your processor is to eliminate as much of this surface imperfection as possible and to produce the best surface contact to your heat sink, and yes this process can and should also be administered to the heat sink as well for the same reasons. This does void warranties and can be very dangerous for our processor if you are not carefull.
What you need
1. Your processor
2. 400, 800, 1000, 2000 grit sandpaper
3. Piece of glass (anything bigger than 2”x2” will work)
4. Rubber gloves
5. Rubbing alcohol and rag
6. Grounding wrist strap
7. Permanent marker
VERY Carefully. If something goes wrong it is very easy to make your processor inoperable. Follow the steps slowly and accurately to avoid as much risk of damaging your processor as possible. (I am not responsible if you damage your hardware.)
1. Put on rubber gloves and an anti-static wrist strap.
2. Carefully clean your processor off to remove any old heat sink compound.
3. Take the permanent marker and draw an X on the top of the processor. Make a medium sized dot in all four corners and in the middle. This will be a reference to check the sanding process and make sure you are sanding evenly.
4. Lay down the glass on a clean table, try to make sure there is nothing underneath the glass to avoid slipping and it’s a good idea to cover the surrounding area to avoid sanding dust from making a mess.
5. Clean the top of the glass off with the rubbing alcohol.
6. Lay the 400 grit sandpaper down on the glass smooth side down and lay the top of the processor down onto the sandpaper.
7. Apply EQUAL pressure to each of the 4 corners at once. This is very important. Not a lot of pressure is needed; let the sandpaper do the work.
8. Slide the processor back and fourth in a vertical motion for about 10 reps.
9. Rotate the processor 90 degrees and repeat step 8.
10. Check the drawn X. If the X is sanding away unevenly rotate the processor with that side forward and slide the processor for a few reps to even out the wearing.
11. Repeat steps 8, 9, and 10 until the entire permanent marker is gone or almost gone.
12. Replace the 400 grit paper with the 800 grit.
13. Repeat steps 8 and 9. Instead of having a permanent marker for visual reference you will have to check for non smooth parts of the processor. This may be hard to see and if necessary just repeat steps 8 and 9 five times.
14. Replace the 800 grit with 1000 grit paper.
15. Repeat step 13.
16. Replace the 1000 grit with 2000 grit paper. The 2000 grit paper is not absolutely necessary however will make the finish as best as possible.
17. Repeat step 13.
18. When this process is complete you should have a very shiny copper toped processor. Clean the processor off carefully with rubbing alcohol.
19. It is highly recommended that you repeat this entire process for the heat sink as well. If the heat sink is not done, your time and work will be wasted because no extra benefits will come out of having only one side of a two sided sandwich done.
20. Compound is still extremely recommended however you can get away with using less now.
21. To achieve the ultimate surface; continue the operation until the processor suctions to the heat sink without the need of any compound. When both surfaces are perfectly flat, they will attach themselves to each other.
I will perform another lap and post pictures at a later time.