Lapped Heatsink temp results

[pegasus1]

Having practiced on a couple of old Skt A H/S i decided to give it a go on my Gigabyte G-Power Pro which is far from smooth, it took about an hour but i ended up with a nice smooth finish with a slight sheen to it. After replacing the H/S and running prime for an hour and giving COD2 a 30 min bashing it dropped 2-3 degrees C after an initial drop of 4 degrees C (the central heating is on now so thats probably why).
Might try it next on my 7800 GTX cooler.

 

[pegasus1]

I've never had the need to lap my hs's. Always nice and smooth and not shiney .

:edit: nice temp results btw

Ive just checked 6 varius CPU H/S's and 3 GPU H/S, all good makes and none could be described as being smooth. When i say smooth i mean looking across the face with a light above and seeing no ripples, scratches or dimples.
Well its now at 35C whilst im browsing the web (in a warm house)which is 1 degree C cooler than it drops too during the day when the house is cold.
Im happy with that

 

[pegasus1]

can i pose a question that has puzzled me
people try to "lap a heatsink" by hand this produces a shiny surface , but is it flat?
is the mating suface of the cpu flat?

if the surface of both have microsopic imperfections ,the the total surface area for heat conduction would be greater than a flat plane
if these ripples ( micro scopic ) are filled with thermal compound then the surface for heat transfer would be greater

thinking about laping a surface unless you use an optical comparitor ( which can read imperfection less than the wavelenght of light ) you cannot be sure its flat , but do you want it that flat

for example two pieces of steel made flat they when slid together will stick ( wrung together )

so after all that do we need these shiney surfaces or will a dull surface conduct heat better

Well professor, the ripples and imperfections i saw didnt need scientific instraments to bring them to my attention. In an ideal world the CPU/heatspreader and HS would be perfectly flat thus needing no thermal compound but as with most things in life this is not the case, i believe that the less thermal compound used, the greater the heat transfer between CPU and HS. I have carried out a scientific experiment and found that my temps are as described above, whether or not you like it, they are the results.

 

[pegasus1]

Nice one mate,

I have an AMD Opteron which takes 1.55v to run at 3.0ghz and the Big Typhoon I purchased for it is far from smooth.

What did you use? Im thinking of buying a lapping kit I saw online here http://www.3dvelocity.com/reviews/pcviper/ultrakit.htm

I read a few guides on the net and then went to halfords and bought the Wet and Dry paper, its not hard but took around an hour.

 

[pegasus1]

used my kitch table.

 

[pegasus1]

after about 20 hours its working 2-3 degrees cooler at idle (34C reported by speedfan/asus probe) but i do have very good case cooling,it was previously idling at 36-37 degrees.