Today I am going to show you how I lapped my Phenom II x4 940 processor!
I know that is much more common to lap Intel cpu's than it is to lap amd cpu's. The two main reasons for this is because amd processors usually already come flatter than an Intel cpu and the other reason is simply because the people that are most likely going to lap a cpu (people looking for extreme performance) are more likely to buy an Intel cpu. I myself have always used Intel processors, in fact this is not only my first lapping job but also my first time going with an amd processor.
Dangers of lapping:
-You will Void your warranty
-You are removing the protective nickel layer on top of the cpu
-You may bend one of the pins during the lapping process
-Do not apply much or any downward pressure on the cpu
-Protect the cpu's pins with the foam or plastic that comes with the cpu
-Take your time
Ok enough of the boring stuff lets take a look at the lapping process
All you need to lap the cpu is:
-The cpu itself
-A mirror or piece of glass
-400 (optional), 600, 1000 (optional), 2000 (optional) grit sandpaper / You only really need the 600grit for a complete lapping, the 400grit make things go faster and the 2000grit cleans up the scratches
-Some electrical tape
-And up to 5 hours of spare time (don't rush)
Now that you have all the materials lets start lapping.
Here is the stock Heatsink and CPU before any lapping.
I made five small markings on the cpu to help see my progress, however it did not really work to well so I do not think it is necessary to do this.
Here is the sand paper taped down on top of the mirror.
There are many different methods for lapping the cpu however I just lapped ten times back a forward in a straight line then rotated the cpu 90 degrees and repeated all the way around.
Here is the cpu starting with the 400grit sandpaper and five minutes of work. As you can see (as it is with most amd cpu's) the edges of the cpu are higher than the middle of the cpu, thus the cpu is concave. I am going to tell you now that this cpu was very concave and it took me over 6 hours of work to get the finished product (I like to take my time).
After 20minutes it is clear that the cpu is concave.
After two hours of slow meticulous work I am hitting the center, however the nickel platting around the center and inside the rim of the cpu remains untouched.
Here she is 3 hours latter still on the 400grit working slowly away, you can clearly see the four most concave areas on the cpu.
Here she is 4 and a half hours latter. You can see the corner with still a little bit nickel on it, this is the most concave (lowest area) area of this cpu.
5 hours in all the nickel is gone and the cpu is much flatter, simply moved up to the 600grit for 5minutes to get a few of those scrachets out, next 2000grit.
Ok so you want shinny, but it is going under that big heat sink whose going to care? Ok fine shinny it is
I used 2000grit sandpaper for 20minutes to get this
Its probably hard to make it out but that is a reflection of the Thermaltake SopranoRS case which is going to be this cpu's home as soon as that motherboard and gpu gets here
Here is the Heatsink and cpu all done. I used the exact same process to lap the heatsink however it was alot quicker because it wasn't near as concave and because it is a lot heavier.
I still have not received my motherboard or gpu so I cannot post any before and after difference. I figured that I wouldn't have the patience to lap the cpu once I got the rest of the computer parts. However as soon as I get the rest of the parts (should be next week) I will post my overclocking resultes and temps with the lapped cpu and stock heatsink on this thread.
I agree that it would have been best to wait so I could compare temps. However since it is already so hot were I live 98F all the time, and since all my computers have always ran so hot all the time I was wanting to get the processor to run as cool as possible as soon as it gets here. Also I believe that I would been to busy testing and playing on the new build that I wouldn't have taken the time out to lap the cpu, and even if I did take the time out I may have rushed it to much. But still it would have been nice to compare before and after temps.