# 3770K IHS removal and results



## graysky (Jul 25, 2012)

*PART 1*
*Introduction*
Feeling somewhat curious about the reports that inferior Thermal Interface Material (TIM) ships from the factory inside Ivy Bridge (IB) chips, I found myself taking my new 3770K out of the safety of its socket this afternoon and on to my desk where it went under the knife. About 15 min later, I finalized the divorce of its Internal Heat Spreader (IHS) and its Printed Circuit Board (PCB).  It was surprisingly simple to do; a standard razor blade (0.009") and a little bit of patience was all that was required.  After cleanup and application of fresh TIM, I sought to put a nice story together for you readers covering how to do procedure yourself and sharing my results and the methods used to arrive at them.

*Removing the IHS from an i7-3770K*
Maintain a level blade and gently insert it between the green part of the chip (PCB), and the silver part (IHS).  I found it best to start on a corner.  From what I've read, care needs to be taken not to scrap the PCB, as key parts of the chip reside very close to the surface.  Slowly and gently, rock the blade between the two until it penetrates.  Then slide it around the perimeter.  See the pics to visualize the die so you don't push the blade in too far.  The IHS will come off easily once you have completed severing the glue which is removed with gentle scraping with credit card or finger nails; isopropyl alcohol doesn't help much.  When finished cleaning up both pieces, apply TIM to the die, place it back in the MB, and gently place the IHS on it.  Lock it into place in the MB with the mounting bracket that will hold the IHS to the chip securely thus keeping you from having to glue down the IHS.











I'm a pretty big fan of Arctic Silver 5 (AS5) and used it both on the die, and on the outside of the IHS.  My "factory" configuration had a good 120 h of load/idle cycles on it.  As you probably know, AS5 has a breakin period associated with it...200 h according to Arctic Silver Incorporated.   One can argue that this claim is valid based on the delta temp data.

*Data Collection and Analysis*
I wanted to generate robust and statically valid conclusions about the efficiency of entire process; results are drawn from a fairly large data set looking at the populations of temperatures and VID values.  Temps and vcore values were collected via lm-sensors driven by a simple shell script which queried it every 2 sec logging the results to a file (see the end of this section for the script).

Example:

```
dts,vcc,temp,core0,core1,core2,core3,120mm_rpm,120mm_pwm,140mm_rpm,140mm_pwm
07-28-12 09:19:31 AM,1.280,66.0,58.0,63.0,65.0,60.0,1285,255,1225,255
07-28-12 09:19:34 AM,1.272,65.0,57.0,62.0,65.0,61.0,1300,255,1216,255
07-28-12 09:19:36 AM,1.272,64.0,59.0,63.0,66.0,59.0,1294,255,1226,255
...
```

These data were annotated and distributions were analyzed to see if the different TIMs under the IHS really makes a difference.  Note that there are too many variable to control for this sort of analysis to be 100 % iron clad.  For example, TIM spreading variations, mounting techniques, variations in hardware, etc.  Even room temp can't be rigorously controlled.  My office is air conditioned and ranged from 75-77 F when I ran the stress tests.  In retrospect, I would have located the PC in my basement which has very consistent ambient temps but hind sight is always 20/20!

*Methods of Stressing*
I use linux, but key stress testers are cross platform.  Intel BurnTest for windows is based on linpack from Intel which is available for many platforms.  The settings I used were 25k problem sizes and 25k leading dimensions with 4 KB alignment.

On top of linpack, I ran a compile job looped in the background (nice=19) set to use 8 threads to further scarfs-up any unused CPU cycles.

*System Specs and Settings*
Asus P8Z77-V Pro
Intel 3770K @ 45x100
Cooling is an NH-D14 with both fans; my system manages their speed but they are both running on max for the stress tests (1,200 RPM for the 140mm and 1,300 RPM for the 120mm).

The BIOS is running using a vcore in offset mode so the vcore is automatically controlled by the BIOS and is dependent on load.  Mine is stable with a setting of +0.0200 and here are the other key voltages and settings in case you're wondering:

```
VCCSA Voltage = 0.92500
CPU PLL Voltage = 1.5500
PCH Voltage = 1.06000
CPU Load-Line Calibration = Ultra High
CPU Current Capability = 140 %
CPU Power Response = Medium
```

*Results*
I ran the stress test described above for ~2 h period and used the geometric mean of the temps per core as the "average" temperature over that time period.  I repeated this for a total of 4 nights, but lost the data on day 1 due to an overwrite on my part!  Here are the average corresponding temps per day; there is a nice decrease out to day 3 where it more or less plateaus off.  Perhaps that is the AS5 "breaking-in."  Also note the error bars correspond to the measured ambient temp which ranged between 75-77 F or 1.1 C.  You can see that some values at day 3 and 4 are not different when accounting for this:




As well, here is a plot of the delta temp, that is, the values subtracted from the stock results indicating the magnitude of temperature decrease:




And to be sure this horse has been beaten well after it died, here are the results compiled in a table:




*Conclusion*
For this example, a decrease in load temps was observed after delidding an Intel 3770K and replacing the factory TIM with AS5.  The magnitude of the temperature reduction was not even across all cores, and ranged for -2C to -12C.  The data are consistent with Arctic Silver Inc.'s claim that the TIM requires a break in period.  This has to be one of the cheapest modifications to gain lower operating temperatures which can be converted into higher voltage and likely higher clock rates.  The unevenness of the decrease is puzzling.  Since the overall rank order of temps was retained after the TIM replacement, perhaps it has to do with some physical unevenness in the IHS, in the base of the HS, or on the CPU die itself.  Investigating this is beyond the scope of this exercise.

*Supporting Data*
Link to my shell used to log the data.
Link to my shell script used to run gcc in the background.
Link to the entire data file (tab separated) should you wish to dig into it.

*PART 2*
*Introduction*
The above analysis was conducted using both a non-lapped IHS on the CPU and a non-lapped heatsink.  I have since lapped both parts and repeated the experiment.  My results seem to confirm that lapping these CPUs give minimal albeit real benefits.  Others have reported no gains.

*Lapping Parts*
The process of lapping in detail will not be reviewed here, but in summary, one uses wet/dry sandpaper and a flat surface (glass usually) to slowly and iteratively grind an uneven surface.  The goal of lapping is not be to make a mirror surface, rather, it is to make _flat_ surface.

Lapping setup:




Heatsink lapping (220 grit --> 320 grit --> 400 grit --> 800 grit --> 1000 grit).  Read this composite pic from left-to-right and from top-to-bottom:




As evident in the photos, the base of the NH-D14 is actually quite flat from the factory.

IHS lapping ( 400 grit --> 800 grit --> 1000 grit).  Read this composite pic from left-to-right and from top-to-bottom:




As evident in the photos, the IHS on this 3770K was quite concave, that is, higher in the middle than elsewhere.  "Flatness" was achieved in this case when no more silver color remained on the IHS.

*Stress Testing*
In addition to the linpack+gcc method described above, mprime (this is the linux version of prime95) running large FFTs was coupled with the same gcc compile stress to give another endpoint.  By default, mprime runs with a background nice level (nice=19) and gcc ran with priority (nice=10).  This is in contrast to the linpack+gcc setup where linpack ran with a higher priority and gcc ran with a background priority.  This was by design.

In the linpack stress, gcc was employed to add further stress since linpack does not stress all cores evenly during a given run.  In contrast, mprime does a very efficient job leveling load across all cores for a given calculation.  Here gcc was given priority over mprime since the very nature of compiling code will lead to uneven usage.

*Results*
Rather than showing a per-core analysis which would make for a rather busy graph (4 cores  x 2 conditions), a more simplistic "Lapped" and "Non-lapped" average results across all 4 cores is shown for each of the stress methods:




The delta temp spread for the averaged results ranged from 0 to -9 for the mprime+gcc experiments and from -1 to -12 for the linpack+gcc experiments.

Each line is relate to the factory TIM/unlapped result represented by the y=0 dashed black line.  Again, these are delta temps which are relative to that factory result.  The pink line shows the average drop in temp across all 4 cores for the unlapped results while the blue line shows the average drop in temps across all 4 cores for the lapped IHS and for the lapped HS.  The data show a real but trivial difference after lapping both parts for most days.  The exception being in the linpack+gcc stress on day 3.  Here the average deltas are within error of each other based solely on the fluctuation in ambient temp.

*Conclusion*
Based on these data, lapping an i7-3370K and the heatsink used to cool it produces minimal benefits in heat dissipation gains.


----------



## TRWOV (Jul 25, 2012)

great job. subed


----------



## adulaamin (Jul 25, 2012)

Looking forward to your results!


----------



## Damn_Smooth (Jul 25, 2012)

Great thread. Thanks for doing this.


----------



## Sinzia (Jul 25, 2012)

Subb'd


----------



## Millennium (Jul 25, 2012)

Just bumping for sub.

Please post results after 60 hours and 120 hours (and maybe something sooner) for comparison 

Also what TIM did you use? cheers


----------



## graysky (Jul 25, 2012)

Millennium said:


> Just bumping for sub.
> 
> Please post results after 60 hours and 120 hours (and maybe something sooner) for comparison
> 
> Also what TIM did you use? cheers



Yeah, I have collected data on 0 h and 12 h so far.  No changes there.
I used Arctic Silver 5.  Yeah, I know there are better ones out there but I had a tube of this on hand and used it.  If the differences are to my liking, I can always pull the HS and IHS, clean them off and repeat with something else like Liquid Pro or Ultra or whatever.


----------



## m1dg3t (Jul 25, 2012)

You beat me to it! lol Nice post


----------



## Frogger (Jul 25, 2012)

SUBed will be waiting for your results.... thinking about an IB upgrade myself ! This might just be the thing to to with a new chip..


----------



## scaminatrix (Jul 26, 2012)

Very impressive. Subbed.

I got some Shin-Etsu thermal tape here from marvelous211's old supply, let me know if you want a bit to try with


----------



## DOM (Jul 26, 2012)

ive done this but wont do it again cuz it doent work to good with ln2 turned a 6.7ghz to like a 6 

but it does help with themps for a reg cooling


----------



## boogerlad (Jul 26, 2012)

You're going to have very bad contact with no ihs because it appears you didn't remove the cpu retention clamp. Also, it appears you have way too much tim for no ihs.


----------



## graysky (Jul 26, 2012)

boogerlad said:


> You're going to have very bad contact with no ihs because it appears you didn't remove the cpu retention clamp. Also, it appears you have way too much tim for no ihs.



Are you addressing me?  I do have the IHS, see pics.  Also, why in the world would I remove the retention clamp?  It is the only force holding the IHS to the die!


----------



## boogerlad (Jul 26, 2012)

Oh sorry, I misread this as running ihs-less. You just replaced the tim. Nevermind then.


----------



## Nordic (Jul 26, 2012)

Another sub.

I read a review some where, where they used Coollaboratory Liquid Pro thermal paste to connect the ivy chip to the ihs. This stuff makes a literal metal bond between the two objects. If I remember correctly, the chip then performed thermally like sandy.


----------



## TheoneandonlyMrK (Jul 26, 2012)

boogerlad said:


> Oh sorry, I misread this as running ihs-less. You just replaced the tim. Nevermind then.



i got gidy untill i got to your post then realised my skip reading robbed me of ten mins damn,
no results yet either tut


----------



## qubit (Jul 26, 2012)

Great thread. I await your results with interest.


----------



## Sasqui (Jul 26, 2012)

^What qubit said!

So the IHS really is a heatsink leveling device.  I'll be really surprised if you don't see some significant temp drops.


----------



## graysky (Jul 26, 2012)

I am already... testing once per night (midnight to 4 AM) and on day 3 I see some good drops that vary from core to core.  There is an effect of seeing thus far, better performance in general on day 2 vs. day 0 and better yet on day 3.  Day 4 is tonight.  I plan to have the data together and ready to "publish" Sunday.


----------



## graysky (Jul 28, 2012)

OK!  First thread updated with data and with conclusions.  Enjoy!


----------



## Frogger (Jul 28, 2012)

graysky said:


> Since the overall rank order of temps was retained after the TIM replacement, perhaps it has to do with some physical unevenness in the IHS, in the base of the HS, or on the CPU die itself. Investigating this is beyond the scope of this exercise.


 Great results 

  ^^^ probably... "perhaps it has to do with some physical unevenness in the IHS"..         you could try lapping the IHS @ rerun to see  result .....but might not be worth the time


----------



## m1dg3t (Jul 28, 2012)

Thanks for updating! Can you compile more info over the next couple Weeks? I have heard some stories of temps increasing over stock after some useage.


----------



## graysky (Jul 28, 2012)

m1dg3t said:


> Thanks for updating! Can you compile more info over the next couple Weeks? I have heard some stories of temps increasing over stock after some useage.



Since I saw that big disconnect in cores 0/1 and 2/3, I actually pulled the HS, cleaned, and reapplied, so the clock has started over


----------



## Sinzia (Jul 28, 2012)

nice job, I cant wait to see what the next round of results will be!


----------



## m1dg3t (Jul 28, 2012)

graysky said:


> Since I saw that big disconnect in cores 0/1 and 2/3, I actually pulled the HS, cleaned, and reapplied, so the clock has started over



Thnx! I'd be doing my own testing but I'm still witout a MoBo.... Damn iTX, no1 cares about us 

I read some posts saying that temps were fine for a few days then shot up, prolly a case of PEBKAC? As I've also heard people say things were fine 

I've had ~10c spreads on every multi core CPU I have seen, must be diodes. I take note of the hottest/coolest and then avg them out lol

I was thinking to run some ThermalRight cf3 instead of as5, I have both...


----------



## OneMoar (Jul 30, 2012)

you got balls of steel to take a razer blade any-ware near a ~300 dollar proc


----------



## Nordic (Jul 30, 2012)

OneMoar said:


> you got balls of steel to take a razer blade any-ware near a ~300 dollar proc



Agreed.
Especially since there is so little info on if their are any benefits to it.


----------



## OneMoar (Jul 30, 2012)

james888 said:


> Agreed.
> Especially since there is so little info on if their are any benefits to it.



heres hopeing he will put the issue to rest I would like to see him try and install the cooler without the IHS  just to see what the temps would be


----------



## Nordic (Jul 30, 2012)

Instead of using the already good noctua, would it of been better to use the stock heatsink. The differences would be more visible. Or would the lack of ability to overclock higher negate that benefit?


----------



## hat (Jul 30, 2012)

OneMoar said:


> heres hopeing he will put the issue to rest I would like to see him try and install the cooler without the IHS  just to see what the temps would be



That would require removing the lock-down bracket seat thing for the CPU... not sure how well that would go over.


----------



## OneMoar (Jul 30, 2012)

hat said:


> That would require removing the lock-down bracket seat thing for the CPU... not sure how well that would go over.



or cut a hole in the IHS > exposing the core


----------



## graysky (Jul 30, 2012)

OneMoar said:


> you got balls of steel to take a razer blade any-ware near a ~300 dollar proc





james888 said:


> Agreed.
> Especially since there is so little info on if their are any benefits to it.



Yeah, it was $340 and that to me, was the price of knowledge I suppose.  Isn't the hallmark of science the ability to independently reproduce an experiment's result?  Plus, I wanted to share details with the community so others could do the same.



OneMoar said:


> heres hopeing he will put the issue to rest I would like to see him try and install the cooler without the IHS  just to see what the temps would be



Yeah, that ain't gonna happen


----------



## natr0n (Jul 30, 2012)

Ive de-lidded a few socket 939. I would always directly cool the core, not puttting the ihs back on.

you get much better temps that way.


----------



## Widjaja (Jul 30, 2012)

natr0n said:


> Ive de-lidded a few socket 939. I would always directly cool the core, not puttting the ihs back on.
> 
> you get much better temps that way.



Yeah I've done the same with an 939skt.
But with those CPUs it was one of the in things to do.
I never got the shims right though so I did the same as the OP and just applied AS5 to the die and resealed the IHS with some stuff which is used to seal car windshields.

Back on topic, it appears the stock TIM may have been applied poorly according to the results which is a concern.


----------



## radrok (Jul 31, 2012)

Subbed, thanks for all the data in here.


----------



## hat (Jul 31, 2012)

OneMoar said:


> or cut a hole in the IHS > exposing the core



The bracket would get in the way. The heatsink won't make contact with the core.


----------



## graysky (Aug 4, 2012)

I updated the first post of this thread with new results having lapped both the IHS and the base of the heatsink.  They start under the section entitled, "Part 2."


----------



## Ikaruga (Aug 4, 2012)

well done, thank you!


----------



## graysky (Aug 4, 2012)

I was able to drop my vcore offset from +200 mV down 150 mV to +5 mV and have a stable system as evaluated by: 5 h of mprime large/FFTs, 2 h of continuous compiling, 2 h of systest 64M, and 2 h of linpack+gcc.  Lower operating temps have their tangibles.  This is @ 45x100.  I'll now switch over to 47x100 to see if I can drop the vcore by a proportional amount and might try 48x100.  Just wanted to update.


----------



## cadaveca (Aug 4, 2012)

graysky said:


> I updated the first post of this thread with new results having lapped both the IHS and the base of the heatsink.  They start under the section entitled, "Part 2."



Thanks for the awesome write-up and work. Seriously, thanks!


----------



## m1dg3t (Aug 5, 2012)

Thnx again graysky! Nice to see the temps remaining level/stable, I guess it was just a couple cases of operator error. I should hopefully have the rest of my parts by the end of this week or next so I can finally get crackin' on my build 

Delidding > Good
Lapping > Not so good

Any plans to test other TIMs?


----------



## Nordic (Aug 5, 2012)

After a quiet difficult google search...
http://foro.noticias3d.com/vbulletin/showthread.php?t=391334
Another person tested with  multiple tims.


----------



## m1dg3t (Aug 5, 2012)

I know there have been other tests, thanks 

Graysky seems to have testing/collecting/presenting down and free of bias, thats why I asked. Plus it's nice for our community to be doing this stuff as well 

 I don't like going out of the forum if I can help it, there used to be some serious dudes around here but not so much anymore?  Things seem to be picking back up a lil' in that area so hopefully it continues


----------



## Nordic (Aug 5, 2012)

m1dg3t said:


> I know there have been other tests, thanks
> 
> Graysky seems to have testing/collecting/presenting down and free of bias, thats why I asked. Plus it's nice for our community to be doing this stuff as well
> 
> I don't like going out of the forum if I can help it, there used to be some serious dudes around here but not so much anymore?  Things seem to be picking back up a lil' in that area so hopefully it continues



I agree on all of that. Just thought some people might like to read it.


----------



## graysky (Aug 5, 2012)

@m1dg3t - Been thinking about using liquid pro on the die but that stuff fuses surfaces together which probably means it would be the last time I did anything to the die so I won't be doing that.  I'm pretty satisfied with my results as-is.  Interestingly, the lower offset (-150 mV) only translated into -1C drop across cores:

Squares are the offset of +0.020 V and circles are the offset of +0.005 V.




Here are a few visuals on the VID distributions.  Remember, my script is sampling 30 times/sec and that on day 4, I dropped the offset by -150 mV:




Here it is in terms of raw counts:


----------

