Lapping, etc.
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apt403
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Pretty much. You use a bunch of different grains of sandpaper to grind down the IHS of the cpu untill you get a mirror finish.
It doesnt cost that much, i mean, all you need is the cpu and some sandpaper, some polishing stuff too if you really want it to look like a mirror.
You might be able to do it. if you screw up its a big screw up, since a screw up would entail pretty much destroying the IHS. if thats the case it would have to be removed for you to continue to use the cpu. If you do remove the IHS you would get better temps, but you wouldnt be able use any heavy heatsinks like the Tuniq Tower or Scythe Infinity without extensive modding because the weight of the hsf might crush the core. Then your REALLY screwed.
If you need every ounce of oc'ing potential from your cpu its totally worth it. Although i would get a crappy $20 cpu to mess around with before you risk it all. There are a bunch of guides out there.
EDIT: Heres a guide by Freecableguy.
http://www.thetechrepository.com/showthread.php?t=71
It doesnt cost that much, i mean, all you need is the cpu and some sandpaper, some polishing stuff too if you really want it to look like a mirror.
You might be able to do it. if you screw up its a big screw up, since a screw up would entail pretty much destroying the IHS. if thats the case it would have to be removed for you to continue to use the cpu. If you do remove the IHS you would get better temps, but you wouldnt be able use any heavy heatsinks like the Tuniq Tower or Scythe Infinity without extensive modding because the weight of the hsf might crush the core. Then your REALLY screwed.
If you need every ounce of oc'ing potential from your cpu its totally worth it. Although i would get a crappy $20 cpu to mess around with before you risk it all. There are a bunch of guides out there.
EDIT: Heres a guide by Freecableguy.
http://www.thetechrepository.com/showthread.php?t=71
Grimmy
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Since Lapping is grinding metal off the surface of either the CPU IHS or the bottom surface of the HSF, I'd say no. Simply if it is your 1st build, you'd prolly want to get the most out of your warranty on certain parts.
Perhaps if you got practice on parts that you don't mind ruining to gain confidence that you can do it right, then that might be worth it, if you do extreme OC'ing. It wouldn't really be worth it running it stock or mild OC's in my opinion.
Perhaps if you got practice on parts that you don't mind ruining to gain confidence that you can do it right, then that might be worth it, if you do extreme OC'ing. It wouldn't really be worth it running it stock or mild OC's in my opinion.
sailer
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Engineering wise, lapping is not smoothing a part to its finest degree, but involves lapping the two surfaces together, ie, the heatsink to the cpu. There are special lapping compounds available for doing this. I've read of different methods of doing this concerning heatsinks and cpus, but never have read of anyone using this method. That doesn't mean it hasn't been done, I've just never read of it.
Yes, it provides a very smooth surface. If done properly, no thermal paste would be required at all. It may help with lower temps, but it may not. It depends partly on how good the surface was before you started. If you do a bad job, the temp might even go up. If you do a bad enough job, you ruin the part.
What I have read is people smoothing a cpu and then the heatsink and putting them together using a thermal paste to fill in any left over scratches. Personaly, I don't think its that easy and unless you've put in a lot of practice with cast off cpus and heatsinks, I'd never recommend doing it. So no, a noob or first time builder should not try it.
In my opinion, its better getting a top quality heatsink and then using Artic Silver ceramic or some other top quality paste instead of going through the lapping procedure.
little_scrapper
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If you do decide to lap do NOT listen to the guy who told you , you should use a metal polish for that mirror finish. That stuff leaves a chemical residue. AND THATS BAD!! The people that use some Weimens metal polish on the CPU is only for the picture to post. If they know what they are doing they then clean it all off with 99% isopropyl befor assmbly.
tool_462
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Don't lap if it's your first build. My Apogee water block is lapped as is my D805 IHS (was fairly concave before.) It isn't expensive or very time consuming if you know what you are doing, the idea is to create two perfectly flat surfaces to mate easily with thermal compound, mirror shine is actually being shown to gain a few degrees over a 600 grit lapped finish.
Oh well, I like the look of my shiny copper D805's IHS
Oh well, I like the look of my shiny copper D805's IHS
brokenshoelaces
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sailer
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This person did a good job with his lapping, in my opinion. I didn't know that the Tuniq Towers had such a bad finish from the factory. They indeed need some work before being used. I note that he used as a 2500 grit sandpaper, which means extra work, but should get an extremely smooth surface. As little_scapper well noted, the surfaces must be cleaned afterwards.
brokenshoelaces
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This person did a good job with his lapping, in my opinion. I didn't know that the Tuniq Towers had such a bad finish from the factory. They indeed need some work before being used. I note that he used as a 2500 grit sandpaper, which means extra work, but should get an extremely smooth surface. As little_scapper well noted, the surfaces must be cleaned afterwards.
i just recieved my premium lapping kit from easypckits.com and am going to use that post on the other forum as my guide. my temps are already low, i cant wait to see after I lap my HSF and IHS.
Grimmy
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Overall, lapping to me is like trying to fix something that isn't broken, although it can help decrease temps.
I can understand those who do an extreme OC, every degree they can get cooled down would be the most important thing to them.
Other then that, the 3-5 degrees (cooler) you can get from lapping, doesn't really matter much for someone like me running stock on some machines, and mild OC on others. Hell... C2D and AM2 or 939 sockets are suppose to run cooler, and some claim to run those CPU with a OCing just fine on air with stock cooling.
Sure it looks cool (getting mirror finish), but how often are you going to take the HS off just to look at the mirror finish, or check out the scraches or imprint the IHS can do to it?
I noticed my Zalman 7700 has an imprint from the hole that is on the IHS from my P4. I think would would have been pissed if I put all that lapping work into it to find scratch or imprints on it. :lol:
But anyhoo... each to their own, what ever trips your trigger.
I can understand those who do an extreme OC, every degree they can get cooled down would be the most important thing to them.
Other then that, the 3-5 degrees (cooler) you can get from lapping, doesn't really matter much for someone like me running stock on some machines, and mild OC on others. Hell... C2D and AM2 or 939 sockets are suppose to run cooler, and some claim to run those CPU with a OCing just fine on air with stock cooling.
Sure it looks cool (getting mirror finish), but how often are you going to take the HS off just to look at the mirror finish, or check out the scraches or imprint the IHS can do to it?
I noticed my Zalman 7700 has an imprint from the hole that is on the IHS from my P4. I think would would have been pissed if I put all that lapping work into it to find scratch or imprints on it. :lol:
But anyhoo... each to their own, what ever trips your trigger.
little_scrapper
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One more note: This is just hearsay from me but I have read alot on this subject and in my readings I found several articles where extensive studies were done to determine the effectiveness of the lapping at different stages. And the oputcome was that these people actually got the BEST results from a 600-800 grit finish. After that, it was stated that the temperature did not improve or even went up a degree or beyond 800grit. I have read several articles and threads stating that a 600grit finish was best suited to arctic ceramic. If you want a pro opinion see if you can get wusy to responde to a PM on this subject.
4Ryan6
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Understand this! If you lap the cpu die, or heatspreader, your WARRANTY is GONE !!!
I would lap the base of the heatsink only if its not smooth.
If the manufacturer leaves an obvious machining roughness to the heatsink base contact surface then I would lap it to smooth starting with wet or dry auto body sandpaper, (possibly) 200 then 400, then to a 600 grit, [I say (possibly) because you may be able to start with 400, or 600, depending on how rough the surface is, you may not have to start with 200], reason being the cpu heatspreader is going to be rougher than a 600 grit polish anyway, so going up to 800, 1200, 1500, and beyond is just a waste of time, money, and elbow grease.
You will still be using a good thermal compound between the heatsink and heatspreader anyway.
By the way, you can polish to a mirror finish with a copper heatsink base, by keeping the paper dry and leaving the copper residue on the paper and continue using the 600grit paper beyond when you think its stopped cutting anymore.
The copper residue left behind starts to polish the heatsink base, metal to metal and if you continue the sanding process it will polish it, I've done it many times.
I first discovered this simply out of desperation, because I'd run out of my higher grit sandpapers, it was late at night, way past dark thirty, and the stores were closed. Ripleys
I would lap the base of the heatsink only if its not smooth.
If the manufacturer leaves an obvious machining roughness to the heatsink base contact surface then I would lap it to smooth starting with wet or dry auto body sandpaper, (possibly) 200 then 400, then to a 600 grit, [I say (possibly) because you may be able to start with 400, or 600, depending on how rough the surface is, you may not have to start with 200], reason being the cpu heatspreader is going to be rougher than a 600 grit polish anyway, so going up to 800, 1200, 1500, and beyond is just a waste of time, money, and elbow grease.
You will still be using a good thermal compound between the heatsink and heatspreader anyway.
By the way, you can polish to a mirror finish with a copper heatsink base, by keeping the paper dry and leaving the copper residue on the paper and continue using the 600grit paper beyond when you think its stopped cutting anymore.
The copper residue left behind starts to polish the heatsink base, metal to metal and if you continue the sanding process it will polish it, I've done it many times.
I first discovered this simply out of desperation, because I'd run out of my higher grit sandpapers, it was late at night, way past dark thirty, and the stores were closed. Ripleys
sailer
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I understand that the finish quality is a subject of controversy. In my above post, I was merely trying to point out the grit size used by the person writing the article. You have a good idea about contacting wusy. Its possible that the different grit sizes relate to the type of paste used as well. I don't know teh answer there, having never personally experimented myself.
sailer
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I think that depends a bit on the surface of the part at the beginning. My Zalman 9500 was very smooth right out of the package, so I doubt lapping it would have made any signficant difference. Tool_462 pointed out that his Apogee was fairly concave, and in one of the links provided, it was commented that a Tuniq Tower was far from smooth. In cases like those, lapping would probably have a marked effect on temperature.
And for sure, as 4Ryan pointed out, you lap it, you bought it for good, cause the warrenty just flew out the window. You might get away with lapping on some heatsinks, but the moment a cpu company saw evidence of lapping, tough luck, too bad, goodbye.
little_scrapper
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My belief is that arctic ceramic's particle size fits very well with a 600-700 grit surface. And therefore give tight cooling.
The copper residue left behind starts to polish the heatsink base, metal to metal and if you continue the sanding process it will polish it, I've done it many times.
Don't you want to clean the copper residue with some Article Silver cleaning compond, rather than to leave the copper reside on the HSF.
Don't you want to clean the copper residue with some Article Silver cleaning compond, rather than to leave the copper reside on the HSF.
4Ryan6
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I think he means when you're sanding it, and you're at a 600 grit sandpaper, you don't blow/wipe off the copper dust that you've scratched off on the sandpaper, but you leave it so that it can scratch up against the heatsink, polishing it.
Yes exactly, but of course when the lapping is completed you clean up the heatsink from all the metal residue before installing it on the CPU.
related lapping questions:
i've been reading that some C2D heat spreaders are actually not flat (i am not talking about roughness). they are concave? (to intel: wtf?!?) i could care less about the roughness of the spreader and heatsink, or what kind of thermal compound is used -- but if the metal is curved on a distance scale > a few mm then there are going to be large area gaps. (i am of the opinion that if there is a measurable temperature difference when using different compounds then you are using too much of it i.e. the distance between the spreader and heatsink is too large either because too much compound is there, or the two surfaces are not flat.) heat sink compound is not meant to fill in such large-area gaps and so i feel like i would want to at least sand it down some.
i have never done this for a CPU before. my questions are:
1. heat sinks assume some specific distance between the board and the top of the spreader. how much can i sand down before the heatsink will no longer fit on tightly? or is this never a problem?
2. i've read some lapping guides but i've never seen any mention of antistatic measures. i've zapped cheap chips just by walking across linoleum on a dry day. i'll be f***Ed if i'm not going to take any precautions rubbing a $300 chip on sandpaper. i plan on grounding myself but can you buy a special socket with all the pins connected together or something? if not, then all the pins are basically floating electrically as i grind away.
i've been reading that some C2D heat spreaders are actually not flat (i am not talking about roughness). they are concave? (to intel: wtf?!?) i could care less about the roughness of the spreader and heatsink, or what kind of thermal compound is used -- but if the metal is curved on a distance scale > a few mm then there are going to be large area gaps. (i am of the opinion that if there is a measurable temperature difference when using different compounds then you are using too much of it i.e. the distance between the spreader and heatsink is too large either because too much compound is there, or the two surfaces are not flat.) heat sink compound is not meant to fill in such large-area gaps and so i feel like i would want to at least sand it down some.
i have never done this for a CPU before. my questions are:
1. heat sinks assume some specific distance between the board and the top of the spreader. how much can i sand down before the heatsink will no longer fit on tightly? or is this never a problem?
2. i've read some lapping guides but i've never seen any mention of antistatic measures. i've zapped cheap chips just by walking across linoleum on a dry day. i'll be f***Ed if i'm not going to take any precautions rubbing a $300 chip on sandpaper. i plan on grounding myself but can you buy a special socket with all the pins connected together or something? if not, then all the pins are basically floating electrically as i grind away.
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