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Core 2 Duo Lapping

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October 11, 2006 8:49:01 PM

If your trying to get every inch of performance out of your Intel Core 2 Duo, but you want to keep your temps down, consider the following:

#1 Lapping the IHS on the Core 2 Duo
http://www.legitreviews.com/article/402/1/

#2 is for Pro's only with tons of money to spare, and works only 1 out of every 4 tries.
http://www.legitreviews.com/article/402/2/

I plan on doing #1 to mine when I get it. :) 
#2 Isn't worth trying on a $300 processor (my opinion)

Then do the same for the Heatsink.

~3LFK1NG

More about : core duo lapping

October 11, 2006 8:58:45 PM

I was hoping part 2 would work... Oh well!
October 11, 2006 8:59:14 PM

Wow, talk about overkill.
Related resources
October 11, 2006 9:01:14 PM

I use to lap my heatsinks, but found that the time I spent doing that, and the temp drop I got, was not signifigant to keep doing it. Plus, I always ended up making a mess in my work area with the all the sanding. The heatsink did look really cool, with the mirror finish, though.

The 2nd technique is just too extreme to try on a brand new CPU. I mean, even the article said that the CPU was toasted, and wouldn't post. Not really worth it, at all, imo.

As for the IHS, I never got a CPU that was convexed or concaved, so I never really lapped the IHS.

I think this is more for the advanced overclocker, since leaving any of the sandpaper residue on the CPU might cause damage, and the 2nd technique is just plain nuts.

:D 
October 11, 2006 9:27:28 PM

I think the temp drop is highly worth the lapping.

If you can knock off 3 degrees by lapping the cpu....an additinal 3-5 with A5S...an additional 5-10 with a After market heatsink, and then an additional 2-3 by lapping the Aftermarket heatsink, thats a total of 13-21 degrees...

Which is fantasic for those of us with high overclocking needs.
Lower heat = Higher overclock
October 11, 2006 9:33:04 PM



8O . o O (I wonder if it was screaming... NO!! NO!! Don't Do It!!)
October 11, 2006 9:38:11 PM

LOL, it probly was felling like it was being interrogated.
October 11, 2006 10:04:25 PM

What a waste of a perfectly good C2D. All for the sake of keeping it a bit cooler. Option 1 seems reasonable (although I'd never attempt it), but Option 2 is just stupid
October 11, 2006 10:07:59 PM

Quote:
I use to lap my heatsinks, but found that the time I spent doing that, and the temp drop I got, was not signifigant to keep doing it. Plus, I always ended up making a mess in my work area with the all the sanding. The heatsink did look really cool, with the mirror finish, though.

The 2nd technique is just too extreme to try on a brand new CPU. I mean, even the article said that the CPU was toasted, and wouldn't post. Not really worth it, at all, imo.

As for the IHS, I never got a CPU that was convexed or concaved, so I never really lapped the IHS.

I think this is more for the advanced overclocker, since leaving any of the sandpaper residue on the CPU might cause damage, and the 2nd technique is just plain nuts.

:D 


I agree with you about lapping, however, posts Wusy has made (with corroborative links) indicate that there is a trend in the core 2 duo heat spreaders to be convex. Whether this is do to a poor die design (mechanical die for stamping the HS, that is :wink: ) or if it was done deliberately to insure good contact between the HS and the die (CPU die, that is) is a question which remains to be answered.

You would be someone who might be able to ask around work about this trend and the cause behind it.

Whatever the cause though, given the possibility of a convex (or concave for that matter) heat spreader, it seems as though lapping may be a good way to go with the Core 2’s
October 11, 2006 11:19:11 PM

Quote:
I think the temp drop is highly worth the lapping.

If you can knock off 3 degrees by lapping the cpu....an additinal 3-5 with A5S...an additional 5-10 with a After market heatsink, and then an additional 2-3 by lapping the Aftermarket heatsink, thats a total of 13-21 degrees...

Which is fantasic for those of us with high overclocking needs.
Lower heat = Higher overclock


I honestly never seen that much temperature difference after lapping.

If you're needing that much more cooling, then I would look at exotic cooling solutions, H2O or phase cooling. Both will cool without the hours spent on lapping, and will significant lower temps of CPU for overclocking.

Of course, that's just a suggestion. I went to H2O a few years ago, but since then, I haven't really been overclocking much. Kind of ironic, that I get a setup to cool in case I overclock, only to not overclock. LOL
October 12, 2006 1:38:54 AM

TEC coolers are unique, and the draw a lot of power, but I guess so does phase cooling and some H2O setups with huge pumps.

I was gonna play with one a few years ago, but I read horrible things when they were done incorrectly (but the same with H2O cooling back in the day). I guess TEC coolers have been integrated with a HSF or even made into a water block nowadays. The heat created by those things are incredible, and having a less than effective cooling setup on them will create a disaster.

I last saw one on a water cooling setup. It was pretty cool looking, but it still was a bit daunting for me to try out.
October 12, 2006 2:27:52 AM

Method #2 was done without any knowledge on how to remove a IHS safely on a C2D.

Experiments from mainly people of XS have shown that the solder melts around 90 degrees celcius. Unfortunately, the solder holding the core onto the PCB is just as easy to melt. To use anything like a propane torch to take off the IHS is overkill. A regular lighter can do the same job and it is much safer to use since it will not increase teh temperature rapidly.
October 12, 2006 2:38:38 AM

Sanding the cpu seems like a good idea ill try that tomorrow. The only part I'm unconformable on is washing the cpu :? is this hazardous? Also does anyone know where I can get a TEC for 30-40$. I will hook it on to my tt big typhoon.
October 12, 2006 2:55:13 AM

Quote:
Sanding the cpu seems like a good idea ill try that tomorrow. The only part I'm unconformable on is washing the cpu :? is this hazardous? Also does anyone know where I can get a TEC for 30-40$. I will hook it on to my tt big typhoon.


Here ya go:

Peltier for sale



Good luck installing it. I would get as much info on condensation and other things before attempting to use one. Also, I am not sure if an air cooled heatsink will keep the heat down. These bad boys generate a ton of heat on the "hot" side.

:D 
October 12, 2006 3:24:28 AM

Holy crap! Does it take 226 watts or is that how much it dissipates. And would condensation occur if the Big typhoon can't cool it down enough? My uncle gave me a pelter cooler before for like a pentium 3 or something. And the only way to get it to condensate was if you stuck the heatsink part in cold water.
October 12, 2006 3:26:21 AM

How bought this one would it have enough power to condensate? And enough power to cool the cpu? And o ya thanks for the link.

Edit: How would I have deal with condensation? What are the steps I can take against it?
October 12, 2006 3:46:56 AM

The cool side gets super cold. It starts to create condensation pretty quickly (on the cool side). I have seen a lot of TEC setups with foam/insulating foam type material around the CPU, to help reduce condensation. It's similar to those used in phase cooling.

About the 226W...I believe that is what it dissapates when it's being used. I'm not 100% about that, since I am no expert with TECs or peltiers. There is place to go, though. Peltier Info

I think they might even have a guide to setup a peltier/TEC setup there, too. Mind you, this guide is a year old, too.

Here's a quick Google link: Peltier Cooling Guides

Again, these might be dated some, or alot.
October 12, 2006 4:45:19 AM

Here are some thermal and electrical specifications for the average 226 watt 50x50mm Peltier device:

Qcmax = 226W @ Th = 27C
Vmax = 15.2V @ Th = 27C
Imax = 24A @ Th = 27C
Pcmax = 364.8W @ Th = 27C


Qcmax is the maximum amount of heat energy that can be moved from the cold side to the hot side. Keep in mind that 226 watts is a best case scenario where you have no thermal losses due to the interface between processors integrated heat spreader and the much larger 50x50mm heat spreader you'll need to mate up to the peltier device itself. Allowing a 50% engineering safety factor, you can probably cool a 80-100 watt Tdp CPU with this device.

Now, at the maximum cooling effect, the total power dissapation of the Peltier device is going to be 364 watts. You need to remove 100% of that heat effectively in order to ensure that the "cold side" stays at 27C in the equation. Removing 364 watts of heat from a 50x50mm ceramic plate is difficult - you'll need a water cooling block indeed to keep your PELTIER hot side cool!


Long story short - it's not worth it for a modern CPU. The best way to implement peltier devices in this scenario are to use 4-5 of them connected to a dual-water block circulation system whereby you have a "cold side" water flow and a "hot side" water flow. The cold side circulates around a waterblock on the CPU, and the hot side circulates through a fan-cooled radiator. That way the peltier devices are not physically located inside your computer, and the duty of transferring heat and funnelling the 400+ watts of power through them can take place externally.

Greg
October 12, 2006 7:47:59 AM

Don't buy just the peltier, with the Monsoon II it monitors everything and alarms in the almost not possible chance that the peltier fails. It also monitors temp to peltier to make sure no condensation is formed. The Monsoon II is the best peltier on the market for that reason.
a b à CPUs
October 12, 2006 2:39:45 PM

Quote:
Here are some thermal and electrical specifications for the average 226 watt 50x50mm Peltier device:

Qcmax = 226W @ Th = 27C
Vmax = 15.2V @ Th = 27C
Imax = 24A @ Th = 27C
Pcmax = 364.8W @ Th = 27C


Qcmax is the maximum amount of heat energy that can be moved from the cold side to the hot side. Keep in mind that 226 watts is a best case scenario where you have no thermal losses due to the interface between processors integrated heat spreader and the much larger 50x50mm heat spreader you'll need to mate up to the peltier device itself. Allowing a 50% engineering safety factor, you can probably cool a 80-100 watt Tdp CPU with this device.

Now, at the maximum cooling effect, the total power dissapation of the Peltier device is going to be 364 watts. You need to remove 100% of that heat effectively in order to ensure that the "cold side" stays at 27C in the equation. Removing 364 watts of heat from a 50x50mm ceramic plate is difficult - you'll need a water cooling block indeed to keep your PELTIER hot side cool!


Long story short - it's not worth it for a modern CPU. The best way to implement peltier devices in this scenario are to use 4-5 of them connected to a dual-water block circulation system whereby you have a "cold side" water flow and a "hot side" water flow. The cold side circulates around a waterblock on the CPU, and the hot side circulates through a fan-cooled radiator. That way the peltier devices are not physically located inside your computer, and the duty of transferring heat and funnelling the 400+ watts of power through them can take place externally.

Greg


Hehehe.. you guys are funny.

The efficiency of a Peltier can be greatly increased by simply cooling the peltier more efficiently. The trick is to create turbulence/friction within the heat exchangers.

Here's are some parts of my setup.. now I don't have any recent pics of these parts installed in the case they're in right now seeing as I haven't taken any pics yet... but the watercooling components are in the same places.



Now the next pic shows when I was putting the whole thing together. This was done back in July and this was before the drop in price on the x1900CF cards which I couldn't resist buying.


Here's another shot of the block..


This is a picture of the same setup but with my DFI/AMD X2 combo I had in there before. I really need new pics.


And the outside of the case..


Now some peeps state that it is impossible to use a 256Watt TEC to cool down an x6800 to bellow Zero temps. That's utter bullox. I idle anywhere between -25 to -20 and load around -15 to -10 at 4.45GHz (using Speedfan as Asusprobe shows 256C and CoreTemp and the Intel software both show 9C no matter what load the CPU's are on). I've done this by slightly increasing the voltage to the TEC and using two pumps and two heat exchangers. I've also increased the turbulence within the watercooling setup by using a large water drop into the secondary heat exchanger.

So TEC's are VERY much still useful. It just depends on how you set the system up to cool the TEC's. As for the case I'm using it's a highly modified Compaq Proliant 1500 series server (it used to house a Pentium 100MHz FYI).
October 12, 2006 4:08:45 PM

Nice setup, Elmo.

Pretty sweet H2O/TEC configuration. What size is that tubing? 1/2"?

Nice.
October 12, 2006 4:49:01 PM

Hmmm...I wonder if perhaps this concave shape to the IHS is teh reason why my temps are pretty damn high even with my Zalman9500?
October 12, 2006 5:14:01 PM

wicked set up elmo!
October 12, 2006 5:22:45 PM

That I say is worthy of a Wusy Award for Excellence and overall cleanness. Here's your trophy :trophy:
I think I'll stick with my Monsoon II though, it works very well even with what I've put it thru.
Then again I might just go straight to a Titan and copy.. erhmm... emulate your setup.

@HYST3R
Nice to see your with the anime gumi now. Love the avatar.
October 12, 2006 6:34:38 PM

Wow! I just sanded the cpu and the heatsink and now my load temps in prime never go above 51 C, it used to go to 56 C. Prime has been running a hour now. Then my Idle temps actually dropped into the 30s C. It used to Idle about 44 C now it idles at 37 for core 1 and 35 for core 2! And the thermal grease still has to set in. The temps I used to have were when the thermal paste was set in.
October 12, 2006 6:48:47 PM

hmm...thats a pretty big damn difference. I guess that means when I go liquid I'll lap the ISH for sure.
a b à CPUs
October 12, 2006 6:56:53 PM

Thanks guys...

Yeah it's a nice setup... I don't use it as often as I would like (only for games). Believe it or not I use my AMD Athlon64 X2 4800+ rig more often and for one main reason... Windows VISTA x64 Ultimate RC2 is just too cool but not yet advanced/stable enough for me to install it on my Core 2 rig... so I run it on the AMD rig.

Now the rig I use the most often is neither of the two.. it's the Pentium !!! 933MHz monster rig with 256MB ram running Windows 95 at work. Oh God how I despise this machine.
October 12, 2006 6:58:30 PM

Since I'm planning on building my first PC in the next couple months, I was wondering what sorts of concerns I should have on lapping a CPU...

Obviously there must be some risk, but besides static/current concerns what else is there? I had planned on lapping my heatsink, but that is obviously far less risky and next to just doing a poor job, you really can not do any permanent harm...
October 12, 2006 7:28:18 PM

Quote:
I was wondering what sorts of concerns I should have on lapping a CPU...

Its real easy all I did was wipe the old thermal paste of with a napkin and rubbing alcohol, then tape the bottom part of the cpu with the pins and such, then started grinding away. When I was done I blew it off with the air compressor took the tape off did it again then wiped it down with alcohol and a napkin.

I think part of the reason it was so hot before was because the center off the cpu was really stamped down. I had to do a lot of grinding to get it even and I mean a lot of grinding.
October 12, 2006 7:31:33 PM

Cheers! :D  I imagine it would be the same process with just more care given and being cautious over currents/static...

Though I imagine this would void any warranty Intel offers... Best test the CPU first...
October 12, 2006 7:53:35 PM

Ya I'm pretty sure I don't have a warranty anymore, but it's been overclocked and running for more than 3 weeks now so it works.
October 13, 2006 1:12:16 AM

Quote:
Wow! I just sanded the cpu and the heatsink and now my load temps in prime never go above 51 C, it used to go to 56 C. Prime has been running a hour now. Then my Idle temps actually dropped into the 30s C. It used to Idle about 44 C now it idles at 37 for core 1 and 35 for core 2! And the thermal grease still has to set in. The temps I used to have were when the thermal paste was set in.


I really can't see this happening. Before lap 44C and after lab 30s C on a TTBT?

I have the TTBT and a 6300 @ 1.35 volts and I idle at 29-31 and max never goes above 40.

I am guessing you had a bad sitting with the HSF.
October 13, 2006 1:30:20 AM

It wasnt 30 C but in the 30's like high 30s. Also It runs a lot cooler than what I said according to the gigabyte temp monitor. But core temp reports like higher temps. And thats what I use because it was made to measure core 2 cpu's. And Everest agrees with it. But gigabytes temps are usually 31 C idle and 46 C full load Prime 95. And the heat spreader was really stamped and it probably wasn't making full contact.
October 13, 2006 6:34:09 AM

I’ve read somewhere Intel makes their IHS’ concave on purpose.

Supposedly the mechanical forces applied after assembly (onto the mobo and then the HSF) should flatten the IHS.

I’m going to try finding some sources on that. According to what I’ve read, there should be documents from Intel on this subject.
October 13, 2006 11:34:15 AM

Thats why I'm going to do a hybrid setup.
October 13, 2006 12:19:07 PM

Ugh, after reading this whole thread, I'm still undecided on whether or not its worth sanding the IHS... It seems like a whole lot of trouble for only a bit of gain, but thats what all of us go through anyways...

Maybe I'll just go watercooling and call it a day.
October 13, 2006 2:21:50 PM

Quote:
Ugh, after reading this whole thread, I'm still undecided on whether or not its worth sanding the IHS... It seems like a whole lot of trouble for only a bit of gain, but thats what all of us go through anyways...

Maybe I'll just go watercooling and call it a day.


Correct if I'm wrong, but isn't that the point? Incremental changes to the temp on your PC? Or at least doing anything you can to bring down the temp? Obviously lapping the CPU, the heatsink or anything else will not be the magic bullet but in the end with everything be equal you will be better off and your PC will be cooler.
October 13, 2006 4:40:31 PM

And further to what I said before... This is a really really cheap way to lower the temp as well...
October 13, 2006 5:11:42 PM

When you combine the following...you get a serious drop in temperature:
Like I said earlier (for those who missed it)
Quote:
Knock off 3 degrees by lapping the cpu....an additinal 3-5 with A5S...an additional 5-10 with a After market heatsink, and then an additional 2-3 by lapping the Aftermarket heatsink, thats a total of 13-21 degrees...


That will provide a huge difference, without having to pay a premium, a total of 13-21 degrees...theoretically. I'de imagine there is a ceiling there somewhere perhaps around 17, but none the less entirely worth it if you know how to do it correctly.
October 13, 2006 5:35:04 PM

It lowered my temps 5- 7 C I think its totally worth it. And my paste still has to set in!
October 13, 2006 5:42:12 PM

Very impressive
October 13, 2006 5:59:11 PM

Quote:
Whatever the reason is, IHS is a bad bad BAD idea.

...

A direct die contact is an absolute must for any modern waterblocks to remove heat efficiently.


But as I recall, aside the cooling effectiveness, the IHS was intended to protect the die from miss handling.

I remember AMD was even criticized in the past on reviews and articles for not using one on their processors (at least regarding protection of the die).
October 13, 2006 6:31:54 PM

LOL Well i am 0-3 on removing the ihs (they were D805's & D915's) so next time it should work I think ill try it on a celeron next time. but i do lapp everything i get my hands on (i did do the e6600) its easy but my first attempt almost backfired


sorry about the quality but you can see the crack i put in it (the green box) Dont ask me how i did it i have no clue.
October 13, 2006 7:15:26 PM

Quote:

Knock off 3 degrees by lapping the cpu....an additinal 3-5 with A5S...an additional 5-10 with a After market heatsink, and then an additional 2-3 by lapping the Aftermarket heatsink, thats a total of 13-21 degrees...


Unfortunately, you can't really expect the benefits of different cooling changes to be additive like that. Benchmark changes are nearly always quoted "ceteris paribus" or everything else being held equal. Because of the way the components of the system interact, changing two or more items simultaneously will almost certainly not give the same result as changing them individually.
October 13, 2006 7:32:34 PM

I would have to agree with Race, its much harder going from 40 to 39 than it is from 50 to 49...

Meh, I guess I'll lap after all. Every little bit helps. Maybe I could outsource my bro to lap for me... there's an idea!
October 13, 2006 7:32:42 PM

Quote:


8O . o O (I wonder if it was screaming... NO!! NO!! Don't Do It!!)


As the review said, this cpu didn't post or work whatsoever.
October 13, 2006 7:45:25 PM

Looks like they should have done part #2 at a slower pace, the CPU could be alive by now =)
October 13, 2006 7:53:48 PM

Don't even try hooking up 226Watts TEC to a Big Typhoon. It will not be able to keep up with the cooling. It will just heat up the cpu. You're better off with the Big Typhoon itself to cool the cpu. Look a cpu (100watts) and TEC 226Watts will give about 326watts heat output in watts. That means the Big Typhoon has to disspate that 326 watts of heat or even more to achieve sub-ambient temps on the cpu. As far as I know the Big Typhoon can cool only to a 100-150 (maybe) watts of heat. So don't even do it with that cooler.
a b à CPUs
October 13, 2006 8:38:11 PM

Quote:
Don't even try hooking up 226Watts TEC to a Big Typhoon. It will not be able to keep up with the cooling. It will just heat up the cpu. You're better off with the Big Typhoon itself to cool the cpu. Look a cpu (100watts) and TEC 226Watts will give about 326watts heat output in watts. That means the Big Typhoon has to disspate that 326 watts of heat or even more to achieve sub-ambient temps on the cpu. As far as I know the Big Typhoon can cool only to a 100-150 (maybe) watts of heat. So don't even do it with that cooler.


True.. best to use an 80W or 120W Thermo-Electric Cooler instead. Also would be good to insulate the processor if you opt to use a more powerful TEC.

Also another thing worth pointing out. If one where to buy this Monsoon II cooler and switch out the TEC, make sure you disable that automatic <25C protection. Otherwise it's useless to get a more powerful TEC if you can't go bellow 25C.
!