CPU/IHS lapping and clip mounts

[DrMrLordX]

Does lapping of the CPU and IHS interfere with clip-based mounting mechanisms, such as the mounting clip used by the Big Typhoon VX on s939 and AM2? I'm only talking about a basic lap job here (200, 400, 600 grit . . . I read somewhere that going beyond 600 grit actually reduces TIM performance).

 

[thecoolnessrune]

I wouldn't think so. The IHS is a mere mm thick, if your taking off enough to mess up the mounting mechanism... I think your already in the core

 

[DrMrLordX]

Good point. You probably lose 1/8th of a mm off the IHS and HSF base by lapping . . .

 

[tylerdustin2008]

You need fine sand paper. The stuff you listed will make it be ruff. I use 800, 1000, and 2000, and if you want even get 2500. These will give you that mirror finish.

 

[DrMrLordX]

I've actually read one document from someone in a lab who was lapping surfaces for thermal transfer through paste, and his findings indicated that the paste did a worse job on surfaces lapped by paper finer than 600 grit.

Granted, he might have been wrong or using some odd TIM, but what he said made a lot of sense.

 

[WoodButcher]

Originally posted by: DrMrLordX
I've actually read one document from someone in a lab who was lapping surfaces for thermal transfer through paste, and his findings indicated that the paste did a worse job on surfaces lapped by paper finer than 600 grit.

Granted, he might have been wrong or using some odd TIM, but what he said made a lot of sense.

I'd love to see that document as I start with 600 wet and then once I've got flat I'll use 1000 or 1200 wet. My temps at load for 6 hrs.

 

[DrMrLordX]

Can't find the original (something about mating metal heatsinks to quartz bases, it was odd) but I found this heated exchange:

http://forums.overclockersclub.com/lofiversion/index.php/t3756.html

psykosis pretty much laid out the same argument the engineer did in the other article I read

 

[WoodButcher]

Originally posted by: DrMrLordX
Can't find the original (something about mating metal heatsinks to quartz bases, it was odd) but I found this heated exchange:

http://forums.overclockersclub.com/lofiversion/index.php/t3756.html

psykosis pretty much laid out the same argument the engineer did in the other article I read

Thanks Dr,
That may explain the prob I'm having now. I just got a new danger den RBX which comes finished to 1200 grit. My pc w/ the RBX idles at 22-25c. I run TAT and it jumps to 45c instantly as compared to the Thermaltake I had butchered for higher flow. 20 idle, 30-34c load. As i said I get FLAT w/600 grit and then finish w/ finer grades, to check my work.
I don't aim for a shine so much as I am looking at the finish to be even. Not spending a great deal time after the 600.
It would not surprise me to find my finished product to be somewhat convex, slightly better contact in the center, hence my good temps with the thermaltake block.

Thanks again DrMrLordX, As I need this RBX for my new configuration it looks like I've got some lapping to do and paper to buy. After reading that I'll use 400, 600 and finish with 800.

 

[idiotekniQues]

i did a lot of reading before lapping - for the IHS you should stick to 600-800 grit as your final run of grit.

now the heatsink, that is another story. go fairly high in grit with this.

 

[GalvanizedYankee]

Read the pdf on the left http://www.easypckits.com/
Note: Figures of 8 and chamfer all sharp edges.

I use full sheets and think it useless to go beyond a well worn sheet of 800 grit.
Use plenty of dish washing soap in the warm water.
NEVER polish with Brass-O or Mother's because temps will rise atleast 1.0C.
ONLY introduce the virgin surface to TIM, he likes virgin metal because the pores are open.

I will not return to or debate in this thread.
Those highly reflective pics posted on children's review sites are for wide-eyed, impressionable kiddies.

 

[idiotekniQues]

Originally posted by: GalvanizedYankee
Read the pdf on the left http://www.easypckits.com/
Note: Figures of 8 and chamfer all sharp edges.

I use full sheets and think it useless to go beyond a well worn sheet of 800 grit.
Use plenty of dish washing soap in the warm water.
NEVER polish with Brass-O or Mother's because temps will rise atleast 1.0C.
ONLY introduce the virgin surface to TIM, he likes virgin metal because the pores are open.

I will not return to or debate in this thread.
Those highly reflective pics posted on children's review sites are for wide-eyed, impressionable kiddies.

lol

well i for one am glad that i did not get too hypnotized by shiny things and kept reading more info

 

[aigomorla]

LMAO, i can honestly tell you, out of all the CPU's i currently own, none is still under warrenty because i lapped them all.

And to answer the correct question in lapping, all guides require you to draw an X on the top die with a sharpie. You then lap enough so the X disapears. (i learned you never start lapping without this because then you cant gauge exactly how much you've lapped.)

So i cant see how you would shave the top down low enough for those stupid 775 retention chips NOT to work, when there a PITA to fit in because there hella tight to begin with.


Uhhhh i hope i made sense with that top statement. I cant seem to make it any clearer.

but anyhow i like my temps lapped.

My Load Temps

unlapped temps were off by 4C.


So i havent had any problems with any cpu yet after lapping. And you shouldnt either if you followed a good guide.

BTW -> i start with 700 -> 800 -> 1000 I make sure i use oil or some lube when lapping as well, unless its an old P4 which has a hole on top of the IHS. Then i use it dry but i do it lightly with more passes.


Off Topic: im sorry i just had to ask. Woodbutcher, WHAT CORE CLOCK SPEED IS THAT 7950GT?!!?!??!? my 7900GT SLI'd at 630 at best goes up to 230 fps on RTHDRIBL. Yours are doing 310!?!?

 

[WoodButcher]

Originally posted by: aigomorla
Off Topic: im sorry i just had to ask. Woodbutcher, WHAT CORE CLOCK SPEED IS THAT 7950GT?!!?!??!? my 7900GT SLI'd at 630 at best goes up to 230 fps on RTHDRIBL. Yours are doing 310!?!?

HAhahaha, LMAO! I'm glad you asked, It was your post of temps that prompted me to post that. My single 7950GT is at 1550 / 600 with "coolbits" That program RTHDRIBL or balls as I've taken to calling it will put a little burn on the GPU but as to the Fps it has too many variables, At 640x480 It will read different fps on each of my displays. Is your monitor Digital or analog? I have a 15" analog lcd and a 19" digital lcd, the digital giving the higher fps. Next you have the multisampling, glare type, depth of field. Play with it you'll see what I mean.

Back on topic, Lapping the RBX block I've got would not help, the block is rectangular in shape and hangs on neighboring caps. Tried it north south and still no way. Maybe if I got a few tubes of TIM,,,, Back to my thermalpuke block for now,, I had to macGyver the loop with a wye but at the moment Asus tells me I'm at 20-22 so I'm not bitching. Shortly I'm upgrading on the mobo so then we'll see what's what.

 

[DrMrLordX]

Originally posted by: WoodButcher

Thanks again DrMrLordX, As I need this RBX for my new configuration it looks like I've got some lapping to do and paper to buy. After reading that I'll use 400, 600 and finish with 800.

No problem, glad to help. It's good to know all the reading I've been doing has helped someone.

Originally posted by: GalvanizedYankee

Use plenty of dish washing soap in the warm water.

Do any variants of dishwashing liquid have scented oils that can work their way into the metal of a heatsink or IHS? I would think not, given the nature of the product, but almost all dishwashing liquid available now has some kind of scent plus other additives.

Also, do you have any recommendations for storing lapped CPUs and/or HSFs for transport or otherwise? I was thinking of a freezer bag or maybe some kind of plastic wrap.

I will not return to or debate in this thread.

Well, I guess I'll just have to take what info I've already gotten then, thanks.

Originally posted by: aigomorla

And to answer the correct question in lapping, all guides require you to draw an X on the top die with a sharpie. You then lap enough so the X disapears. (i learned you never start lapping without this because then you cant gauge exactly how much you've lapped.)

Thank for reminding me.

So i cant see how you would shave the top down low enough for those stupid 775 retention chips NOT to work, when there a PITA to fit in because there hella tight to begin with.

Yeah, thecoolnessrune said the same thing (for the most part). Thanks for answering though.