• Welcome to Overclockers Forums! Join us to reply in threads, receive reduced ads, and to customize your site experience!

Lapping? or not...

Overclockers is supported by our readers. When you click a link to make a purchase, we may earn a commission. Learn More.


Jun 2, 2001
Hi all, just a question about lapping. So, is it better to lap just the heatsink or both the heatsink and the cpu? Are there any problems that can arise from lapping (or trying to) the cpu? If I lap both the cpu and the heatsink, will putting thermal grease between them make things worse?


I have a celeron 366 with a golden orb. Sorry, the orb was bought before reading and I can't really get rid of it, though it was all I could get for the money I had. Just reading that cheap heatsink article, but on thermaltake www site they say the c/w for orb370 is 0.91!
Could this be why it's so crappy?

I have no experience with celerys but I have had good results lapping both the HS or waterblock and the CPU. The final lap was with Artic Silver as the lube on 2000 grit paper. Be sure to apply thermal grease of your choice before assembly.
The only thing that could go wrong with lapping the celly is if you damage the core...you have to be careful.
Start it with 1000 grit or finer if you can get it.
make sure you sand on a flat flat surface, ie. a mirror or a piece of glass...and also, alternate the direction you sand in so that you don't over sand one area, like do a figure 8 motion on the wet sandpaper or alternatively up and down and then side to side.
Resist the urge to sand any small blemishes individually. I mean if there's one small spot that's sticking out, don't just take the sandpaper & sand that one spot.
The surface has to be even to ensure a good connection between the cpu & heatsink.
Thermal paste is good and won't harm your cpu..providing you don't overuse it..you don't want it gooping out the sides.
Just a thin thin layer is fine....I spread mine with a straight razor and take off any excess if there is any.

and no need to be sorry about your choice of heatsink...the gorb is nice to look at and I'm sure it will perform just fine for the celeron...just keep an eye on the temps..you're the same person with the corners sticking out, are you not?
If you decide to lap your processor, don't forget to isolate the chip from static and sanding dust. Most people put their chip in one of those static bags computer parts come in. They then cut a hole in the bag to allow the core to come through and seal it off around the core.
I would suggest 2000 grit for lapping the CPU and a good 20 power loop to check your progress every 30 seconds. Lapping a CPU is not for the faint of heart.
I don't recomend lapping the new P3's, Celeron 2's, and Athalons as they are already in good shape from the factory. The old celerons are a whole nother story. At .25 micron the die size is very large and often times is far from being flat. I have dual 366's on a BP6 running at 572mhz with Alpha pal 6035's. One of these chips was so bad that when held up against the HSF it only touched 2 of the outside edges and light could be seen over the top of almost the whole core. Lapping made a big difference in this cpu. Check yours and see how flat it is. If you decide to do it just be carefull and take it slow if you go to far it'll be a keychain. I am sure if you do a little digging you can still find a few lapping howto's with pics of the old celerons. Lap the heatsink to and yes still use grease.
colin...I've seen a couple post here and there with fellas recommending the as2 lubin' the final paper. What is the point of this? If the final paper is AlOx or Carborendum it seems you'd just be making a slurry of contaminated as2 that would fill the micro pores.

If your then cleaning this out,won't a cheaper lub,like water, do just as well? Just curious.