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

God's gift to heatsinks

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

Sinkhole

Registered
Joined
May 19, 2003
Location
Hamden, CT
I have an older heatsink, a GlobalWIN FOP-38 and what a differance lapping it made. WOW...Lapping is truely God's gift to heatsinks. Im currently reading much lower temps than before.

Before Lapping
Idle: 35°C/95°F
Load: 47°C/116°F *


After Lapping
Idle: 32°C/89°F
Load: 36°C/96°F *


* = Load temps taken while running Toast for 30-45 min

Sink
 

cf79

Member
Joined
Apr 5, 2002
Location
Denver, CO
That is a very nice diffrence. Eleven degrees off a load just from a lap? Very impressive. I bow to you good sir..

handsdown.gif
 

q149

Member
Joined
Nov 10, 2002
Location
Japan
Yes, lapping can make a really huge difference on heatsinks that arent so good. I got results close to that with a stock amd heatsink a while back.
 

trdsw20

Member
Joined
Jan 9, 2002
Location
bay area
You might want to wait for the thermal interface material to settle. Thats usually how it is when you first apply it. wait a week and see what it comes down to.
 

cf79

Member
Joined
Apr 5, 2002
Location
Denver, CO
WhOdini and Mico... Check out the Lapping guide located in this sticky thread. It involves sanding down the HS base to make it more even and smooth (for at stock, there are little groves on the copper plate which means heat is escaping in the transfer)..

The most I got out of lapping is about 4 - 6 degrees.
 
OP
Sinkhole

Sinkhole

Registered
Joined
May 19, 2003
Location
Hamden, CT
I'm so damn impressed !! It did take awhile to do and the ole elbow is like falling off now, but it was well worth it. I also went with alot less Artic Silver than before. I think I may have been over loadin on the stuff.

Sink
 

greywood

Registered
Joined
Aug 4, 2002
Location
Blue Bell, Pa
Hey guys, here is a short "How-To" for heatsink lapping.

Materials needed:

1. A good flat piece of glass or mirror (maybe about 6" x 8").
2. Wet/Dry sandpaper of of several different grit-sizes
I generally start with #320 if the heatsink surface is uneven
or feels rough to the fingernail (machining marks). Then,
I'll go to #600 or so, and maybe finally to #900 or #1000.
If the heatsink is already fairly smooth, you may be able to
start with, say #400 grit and stop with #600.

Process:
1. You don't need a "mirror-like" finish - what you want is smooth
sheen and flat, with no scratches or machining marks left.
2. Soak a partial sheet of sandpaper in water, briefly then lay it
out grit-side up on the glass; keep it drenched all the time.
You may even want to rinse off metal particles under the
faucet occasionally, to keep a good grinding surface.
3. Gently rub the working surface of the heatsink on the paper
in a circular or figure-8 motion. You don't need to press hard;
keep the paper wet and let it do the work. Every 1-2 minutes
rotate the heat-sink by 90% trying to wear away the surface
evenly, so it comes out flat.
4. Check results after 5-10 minutes with the first grade of paper.
When you've gotten rid of all the machining marks, move to
the next finer grit-size and continue, until you're satisfied
with the results.

5. Just remember, you don't need to grind away "half the metal"
you just want a nice smooth, flat surface to mate to your CPU.
Depending on how good/bad your heatsink is to start with,
this process might take anywhere from 20 minutes to an hour.

6. When you are done, carefully clean all the grit and crud off the
heatsink with something like rubbing alchohol or acetone.
Clean the surface of your CPU core the same way.

Don't Touch the CPU or heatsink surface with your fingers -
no matter how clean you think they are you'll leave skin oils
on them and that will hurt your cooling results.

7. With a clean razor-blade or straight piece of stiff plastic,
spread a THIN layer of Arctic Silver-3 on the CPU core.
A small glob about the size of a grain of rice will be way 'nuff.
Then, mount the heatsink, being careful not to smear the
AS-3 around.

That all there is to it. When I first did this with an old AMD T-Bird
chip that was running darn near 60C, it got me about 8C cooler.

Have fun, and be cool!
 
OP
Sinkhole

Sinkhole

Registered
Joined
May 19, 2003
Location
Hamden, CT
I started off with 320 grit wet/dry then moved on to 600 grit wet/dry when after it was roughed in and finished with 1200 grit wet/dry. This gave me a pretty sweet finish. I also lapped the stock Northbridge heatsink while it was off, man was that thing wavy. I tried to fit a Blue Orb in its place but I didn't want to fool with pushing the capacitors around. Im sold on lapping now and am going to lap every heatsink I own.

Sink
 
OP
Sinkhole

Sinkhole

Registered
Joined
May 19, 2003
Location
Hamden, CT
I know it sounds like alot and I am kinda new to this OC'ing thing, but I can only tell you, honestly, what figures I got from MBM 5. ASUS Probe reported the same figures. I also feel the thermal compound issue had an affect on it. As trdsw20 said maybe after a couple days it might settle in. I dont know if it actually does that sort of thing. But I am gonna run Toast overnight and let MBM5 record the whole deal and see what happens. I only ran it for about 40min. before but it had seemed to stabilize. We will see in the mornin.

Sink
 

sanford1

Member
Joined
Apr 7, 2003
Location
Vero Beach, Florida
greywood said:
Hey guys, here is a short "How-To" for heatsink lapping.

Materials needed:

1. A good flat piece of glass or mirror (maybe about 6" x 8").
2. Wet/Dry sandpaper of of several different grit-sizes
I generally start with #320 if the heatsink surface is uneven
or feels rough to the fingernail (machining marks). Then,
I'll go to #600 or so, and maybe finally to #900 or #1000.
If the heatsink is already fairly smooth, you may be able to
start with, say #400 grit and stop with #600.

Process:
1. You don't need a "mirror-like" finish - what you want is smooth
sheen and flat, with no scratches or machining marks left.
2. Soak a partial sheet of sandpaper in water, briefly then lay it
out grit-side up on the glass; keep it drenched all the time.
You may even want to rinse off metal particles under the
faucet occasionally, to keep a good grinding surface.
3. Gently rub the working surface of the heatsink on the paper
in a circular or figure-8 motion. You don't need to press hard;
keep the paper wet and let it do the work. Every 1-2 minutes
rotate the heat-sink by 90% trying to wear away the surface
evenly, so it comes out flat.
4. Check results after 5-10 minutes with the first grade of paper.
When you've gotten rid of all the machining marks, move to
the next finer grit-size and continue, until you're satisfied
with the results.

5. Just remember, you don't need to grind away "half the metal"
you just want a nice smooth, flat surface to mate to your CPU.
Depending on how good/bad your heatsink is to start with,
this process might take anywhere from 20 minutes to an hour.

6. When you are done, carefully clean all the grit and crud off the
heatsink with something like rubbing alchohol or acetone.
Clean the surface of your CPU core the same way.

Don't Touch the CPU or heatsink surface with your fingers -
no matter how clean you think they are you'll leave skin oils
on them and that will hurt your cooling results.

7. With a clean razor-blade or straight piece of stiff plastic,
spread a THIN layer of Arctic Silver-3 on the CPU core.
A small glob about the size of a grain of rice will be way 'nuff.
Then, mount the heatsink, being careful not to smear the
AS-3 around.

That all there is to it. When I first did this with an old AMD T-Bird
chip that was running darn near 60C, it got me about 8C cooler.

Have fun, and be cool!

I'll quote it for emphasis.... That is one of the best primers on lapping a heatsink I've seen in print. Deserves a sticky IMO.
 

Jah Warrior

Disabled
Joined
May 25, 2003
Location
WWFC 4 ever
First off i used 400 grit then went up to 600 unfortunately 1000 grit wet n dry is not so easy to find in my home town so I used some brasso on my SLK900 and it gave it an almost mirror finish, temps dropped a further 2 degrees over the standard temps with Thermal paste applied in the same manner as i always do (with a spade) :D