Lapping the 2.4C IHS

[Liquid3D]

Thank you Mr Thompsom for the Overclockers.com link. The article for me, transcends prima facie dicussion of "flatness" under load. I beleive there's a more important, underlying lesson here. As Enthusiasts, much of what we do, is experimental. Therefore it should meet a testable criteria. There are different types of truth. A specific claim is either an empirical generalization, for which there is wide scale conformaton. Or a "conceptual truth" derivable from our concept of invention. The latter is a more abstract, creative process, the former much more important for our purposes.

My post above is hypothesis, based on certain knowledge of CPU architecture, however; it eschews any emprical confrimation. This does not necessarily detract from it's possibility, however; lack of any testable criteria, does detract from it's probablity. It's based upon Inductive Logic. Where a universal conclusion, is derived from a specific fact, or observation. The problem with the Inductive argument (modes ponens)is that it suffers from what is know, as an, "Inductive Leap." In other words, at some point we must "presume" based upon a tenative hypothesis, which itself is based upon, one or more observations. It's more creative, then empirical.

Albeit Deductive (Modes Tollens), Inductive (Modes Ponens) or Catagorical, as Enthusiats, we should be employing logic in our testing, of hardware. Only in this manner can we have a conversation with a common frame of reference. Otherwise were simply talking from the side of our necks.

If I'd taken my IHS, and merely lapped it with my finger, then I'd have no idea, if the sutrface was uniform or not. I actually disgree, with Intel's ad hoc remedy for the variences among heat spreaders. Not becauise it isn't the best remedy, but i wonder if it perpetuates complacency on the part of Heat Sink manufactuers, not to be overly concerned with flatness? I can see why Intel has done what they have, done, and had mr Thompson not provided us with the link, I wouldn't have known "all" P4 IHs were designed in this manner. Just about every person responding to this thread, seemed to experience the same phenomenon while lapping. They found the center wore away more rapidly the the sides. Yet on my ffirst 2.4C, the opposite occured. I'm too tired to use an example of Syllogistic logic here, but why don't you try? For example;
Premise-1: When lapping a concave IHS, the center will be exposed first
Premise-2: The P4 has a concave IHS.
Conclusion: Lapping a P4, results in center exposure first.

[nikhsub1]

I just removed my heatspreader altogether today and here is why... Each and every time I would take off my water block, the CPU would get stuck the the water block so strongly that it would yank the CPU right out of the socket, almost like the thermal paste created suction. The only way to get the CPU off the block was to slide it all the way to the edge of the block. Today, when i took my block off, it yanked the CPU out but this time, bent several pins. Now I was pissed. So, I got a straight edge razor blade and a pair of plyers and slide the blade under the spreader at each corner. The thing came off like butter. I cleaned it up. put some paste on the die, fixed the pins and put the block on. I was prepared for a dead CPU, either from the pins or taking the spreader off. Sure enough, it booted up no problem. My temps are now 4C lower. A good result I think. I also lapped the heatspreader down to the copper weeks ago, but saw no improvement over doing so.

The reason why I may be seeing such a big drop in temps without the spreader is because of the WB im using, the Cascade which is VERY focused.

Anyone know if the P4 die is more fragile than an AMD die?

[Liquid3D]

I belive the P4 core is much more so then the AMD, as it was designed differently. AMD obviously designed their core, with the intention of having the heatsink pressure directly on it. Not only that, but any designer worth their weight in solder, is going to design some extra duribility, to compensate for operator error.

I have the same exact problem everytime I remove the P4. It depemds upon which thermal transfer material you use, and how much is applioed. My ABit IS7-E, and IC7-G (for example) couldn't hold the CPU down while I removed the hetsink, the Epox 4PCA3+, has a more secure locking mechanism, and the CPU rem,ains frimly in plce when i remove the HS. Glad you brought this up. It was really bothering me, until i tried another board. I was concerned, in the locked position, pulling off the HS, may even pull pins out, and damage the CPU. I also had to slide it several times.

[nikhsub1]

Originally posted by Liquid3D
...Glad you brought this up. It was really bothering me, until i tried another board. I was concerned, in the locked position, pulling off the HS, may even pull pins out, and damage the CPU. I also had to slide it several times.

Yeah well I figured if i left the Heatspreader on, i would surely kill the cpu by bending/breaking pins off the bottom and that would suck. I guess I'll take my chances without the spreader, but I do like the temp drop! Gone with the CPU condome!

[Liquid3D]

Let me say it now, because someone will. "Your not praciting safe CPU-sex (overclocking) and you never know what you could catch (overheating)."

[nikhsub1]

With the recent heatwave in Los Angeles (95-100F) I have been forced to bring down the OC to 3450. Now with the heatspreader removed, my temps are rediculous! And this is an IC7 which people claim reads high. Room temp is about 29C.

[STEvil]

Lol liquid 8-)

[DoGMaN]

Liquid3D you can see from the pic I posted that my IHS was not high in the center either. Rather much higher on the outer edges. That particular pic is of a 3.0C not a 2.4C but that shouldn't make any difference.

[Peen]

nikhsub1 can u explain a little bit on how you u did it? some ppl say its tff getting it off, and i would like to take OFF my heatspread and stick some good thermal grease in there

[Major]

IMO it might make it easier to pop off the IHS if you put the chip in the freezer for a while. (It works with other thermal adhesives) Now that I have an extra chip I'll probably take the hs off the 2.8c and see what difference it makes too.

[nikhsub1]

Originally posted by Peen
nikhsub1 can u explain a little bit on how you u did it? some ppl say its tff getting it off, and i would like to take OFF my heatspread and stick some good thermal grease in there

It is pretty easy, I dont thing the freezer is a good idea, that will make the epoxy brittle, you want it soft. I used a regular razor blade, a brand new one so it was sharp. I used a pliers to hold the blade. I then slid the blade under each corner of the spreader and gently made sure that i cut all the epoxy. Just take your time, and use a new blade and it is a sinch. Once you cut the bond of the epoxy, the spreader will fall right off. You will freak out on how light the cpu is without the spreader.

[Liquid3D]

nikhsub1 how high have you had that 2.6C, i'm thinking of adding a 2.6C to my collection, but was told as the chips increase in speed, they don't OC as well. Of course their all the same core .13-micron die, architecture, same Masks (templates), Photolithographic process (248nm), wafer's (200mm, and 300mm?) and only bined by multiplier, and vcore. Obviously Intel hit a home-run with the Northeood-D as they'll overclock at default vcore to 3.6GHz and above, and minme OC'd to 3.6 at defualt, and only ran at 36C. Just imagine if the NB and/or memory weren't holding me back? That's one advantage of the higher multipler, CPU clock speed, lower multi bandwidth. Their all most likely capable 3.6GHz, the only thing holding back my 2.4c fom 4GHz is it's multiplier is too low. The 875NB-MCH just can't clock over 300FSB very well without customizing something. My Abit would clock better then my Epox, had it more then 2.8VDIMM, and perhaps my Epox would clock better then my Abit had it higher then 1.6Vcore, and active cooling (although I've yet to feel my NB-HSF even warm).

dogman yes, it's very strange that article discussed Intel's designing the IHS concave to compensate for any variances among Heat Sinks, but I find this may not be entirely accurate as both of us had IHS's which were higher at the edges. Of the two I have, one is higher in the center, and the other the edges? That's not consistent in any respect? I'm taking off the IHS like I told Major two weeks ago, I procrastinated because I'd had so much succcess, but it's time to find some thread.

The safest way I've heard of removing the IHS, is to take a piece of thread, and saw through the epoxy. It's time consuming and strong thread is required, but it doesn't get much safer.

[uclajd]

Originally posted by nikhsub1
I just removed my heatspreader altogether today and here is why... Each and every time I would take off my water block, the CPU would get stuck the the water block so strongly that it would yank the CPU right out of the socket, almost like the thermal paste created suction. The only way to get the CPU off the block was to slide it all the way to the edge of the block. Today, when i took my block off, it yanked the CPU out but this time, bent several pins. Now I was pissed.

Actually, pissed is understating it. I had the same phenomenon with my Volcano 7+ and Shin Etsu - I ripped the processor right out, without benefit of the lever. I don't care how well that $#!t cools, never again do I use Shin Etsu.

I think it killed my socket/board, because it was dead when I put my watercooler on. I swapped the 2.4c for a 2.53b, still dead, not even a beep. I dropped the 2.53, RAM, HDD, vid card into my old IT7, and it worked fine.

So I RMA'd the less-than-a-month-old P4P800DX, which I am waiting to get back. A hard-learned lesson. No apparent damage to my beloved 2.4c, which clock to 3.46 3D stable - on air - thank God.

Rather than ripping off the IHS - which I know would surely lead to me crushing the core for an encore - I'm thinking Nanotherm PCM+ for when the board comes back - does anyone know if this stuff is sticky?

[Peen]

I think im going to take off my heatspreader, but put it back on with AS3 cause with my luck the core will crack. I might just try to smooth out the bottom of the IHS with 600 grit maybe. Im still scared to take off the IHS also

Also about what someone was saying in the post above( cant remeber who) about the fact that when you sand it that the HSF doesnt apply as much pressure. This would be much more of an issue with no IHS

[Peen]

ok i took off my heatspreader too! it was easy as hell, right when u get under the IHS you dont even need to saw with a razorblade. Just a light push and its like the glue just peels. Anyways the grease that was under the CPU was hard as a rock. I also bent a few pins and they are OHHH so close to falling off , and the CPU is light as crap without the heatspreader.
As for temps? i didnt get a temp change yet, maybe cause its new AS3

Edit:6c drop in temps so far under full load

[PTK]

When you take off that IHS, how do you get that "rock hard" Intel original grease off ? I was thinking about lapping the IHS, but why not go all the way

PTK

[nikhsub1]

I dont know that I recommend all of you take the spreader off! I did it because of what was happening with the cpu getting yanked out of the board, no other reason. I have been told that the die is very fragile so if you do this PLEASE be extra careful when mounting your cooling device.

[Nanotherm]

uclajd,

No, the PCM+ is not sticky. Just a quick note on the re-application of PCM+: Since the PCM+ forms a semi-solid, wax-like coating on and between both mating surfaces (which is how it's supposed to be) after application, you should remove your HSF or Waterblock within a few minutes after shutting down your PC while the CPU and HSF are still warm.

[uclajd]

Originally posted by Nanotherm
uclajd,

No, the PCM+ is not sticky.

Thanks, Nanotherm.

Anyone who doesn't work for Nanotherm have a take on this stuff?

[Peen]

yeah but the temp drop is worth the taking off of the IHS. Plus i know i wont crack the core

[nikhsub1]

Originally posted by Liquid3D
nikhsub1 how high have you had that 2.6C, i'm thinking of adding a 2.6C to my collection, but was told as the chips increase in speed, they don't OC as well.

I have had this CPU up to 3.7Ghz on my water in sig. This was when the ambient temps were much more reasonable...

[Liquid3D]

Well I certainly think the higher multipler will benefit me. 12x is great for bandwidth, however; if one is looking to attain the processors speed limit, multiplier should be high. But I couldn't afford a 3.2C (heck I cant even afford a 2.6C have to find a trader).

[Marvin]

The new stepping p4 IHS is harder to remove. As my 2.8 is a SL5WJ, i will try that tomorrow.

[Liquid3D]

I wouldn't recommend removong the IHS from any current P4's. Using any method string or otherwise.

I beleive their now using a silver-epoxy just under the IHS on the core, and it will destroy the chip when you pry it off. This is true with the P4 EE's and I have a feeling the chage may have been made across the board as it would certainly increase thermal transfer.

You can, however; still lap the IHS to a mirror finish, and I HIGHLY recommend getting a kit from http://www.easypckits.com I got one and below is the result. That's my surfboard in the reflection on the left, and the right is focused on the chip. Almost as pretty as your avatar my friend;

[Marvin]

heheh, really almost.
So after reading this excellent topic, billa´s article and procooling topic, i came in some ideas:
1 The IHS is really concave(mine)
2 if you try to lap do it the right way.
3 Adjust your presuure clamp.
But how intel only assegure 15-20 mountings ?
sorry my english.
hey, off topic my under contrction water box.
soory my crappy english