Do you lap your CPU?

I lapped my Q9550 and TRUE and it shaved several degrees off the temps.

The method I used was to first use course sandpaper (250-300 grit if i remember rightly), stuck to an unused glass picture frame (to ensure the surfaces were flat). Then move the CPU and later the TRUE up and down the paper the paper wore out or the surfaces were flat (tested with a metal ruler).

I then repeated this with finer grain (800 grit I think) to make it look nice and shiny.

Whole process took a few hours and dropped the CPU temps by a few degrees.


I considered it with my current i7, but I really wanted to keep the warranty intact. I may well give it a lap in a year or two.
 
I don't because I'm too lazy (and slightly worried I'll **** it up :p). Also never had too much of an issue with my overclocks so haven't really felt the need.
 
I lapped the q6600 i had, and my TRUE, 400, 600, 800, 1500 and 2000 grade grit. Knocked about 5-6c of the temps, in combination with higher rpm fans, this allowed me to up the oc on the cpu from 3.6ghz to 3.8ghz, temps stayed the same as 3.6ghz, 68-68-62-62. Still use the lapped TRUE, but i dont think ill bother lapping the i7.
 
What is lapping the CPU and True? and how does it benefit us? is it hard to do? any risks behind it?
 
Basically you sand the surface of the cpu to flatten it out, TRUE means thermalright ultra extreme, a high end air cooler. Lapping both surfaces ensures a better contact and can reduce temps. Theres no risk lapping a cooler, but with a cpu if you take your time and approach it carefully youll have no issues, however you loose your warranty.
 
nlr said:
What is lapping the CPU and True? and how does it benefit us? is it hard to do? any risks behind it?
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This is lapping. In relation to CPU it means making the metal CPU heatspreaker and the CPU heatsink base plate (the bit that contacts the CPU heatspreader) as flat as possible.

As many CPU heatspreaders and CPU cooler bases are somewhat convex (fatter in the middle) then the thermal contact between the two is often not ideal. In theory, lapping the CPU and heatsink should mean that the two are able to have good thermal contact across the enitire surface area of the CPU heatspreader - thus maximising heat transfer away from the CPU and keeping the CPU cooler.

The risk is that you screw up and kill your CPU or break into a heatpipe of the heatsink (I would love to see that happen). Not very likely unless you go mad (ie not stop when it first becomes flat).
 
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I have seen a few direct heatpipe coolers destroyed by some over zealous lapping, left the pipes so thin that when mounted and put under pressure they cracked. No such problems though with a cooler such as the TRUE.
 
Why does it have to be true? theres much more better cooolers like the noctua? and how much difference does it make to lap your cpu?
 
It doesn't have to be a TRUE, it just so happened that both me and setter have these coolers - and a few years ago there was no Noctua NH D14, the TRUE was the best cooler around then.

As for lapping them, the TRUE is good, but very often the base isn't close to flat - so lapping it can yield big performance gains. From what I have seen, the bases on the Noctua coolers are produced very flat, so the benefit of further lapping the heatsink would not be great.
 
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AFAIK the Intel stock heatsinks only contact the CPU in a relatively small area in the centre of the CPU. Hence, making a convex heatspreads makes a bit of sense in this case, also it will help prevent air bubbles being trapped in the thermal paste.

However, if you have a third-party heatsink that can fully cover the heatsink, this shape is not ideal.

As for pre-lapping them - well lapping is a mechanical process, if each CPU heatspreader had to be precisely milled, it would increase CPU costs for little improvement at stock speeds.
 
Its not hard as in complex, but it does take some elbow grease and a bit of time.

Is it worth it? It really depends on your CPU, heatsink, current max. load temps and your overclocking ambitions.
 
cmndr_andi said:
Is it worth it? It really depends on your CPU, heatsink, current max. load temps and your overclocking ambitions.
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Indeed, depends if you think a few degrees and possibly a couple of hundred extra MHz is worth a couple of hours + however much it costs you to get the wet & dry paper. :p
 
1LANCS said:
<3 Sarcasm.

For the sake of a few degrees for the average person its not really worth it, if you really want a few degrees cooler invest in watercooling or better watercooling kit.
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Then you just get the same argument with lapping your CPU block and CPU ;)
 
I personally have never lapped any of my CPU's. I can see there may be some benefits in doing this but I can't help thinking Intel put a nickel coating on the Heat spreader for a reason. :D
 
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