Lapping a Core 2 Duo - How To?

[darkspreader]

I've read up a little on it, but I don't know if I should or not for my overclocking enviroment.

I have an e4400, and I plan to overclock it to 3.0ghz. I have a Scythe Infinity that I am going to mod, following this guide, and also put a push/pull fan config on it.

Are there any suggestions on if I should lap my e4400 or not, and if so, how would I go about doing it? All I know is that you start off with a low grit, then finish with a high grit.

Also, should I lap my Infinity the same way?

Thanks.

Edit: I layed the e4400 on top of my heatsink after I cleaned both surfaces with ArctiClean 1 + 2, and I noticed that there is a sort of suction when I pull the e4400 back off. That tells me that the surface of the e4400 is pretty damned flat, right?

 

[SuperFly03]

I layed the e4400 on top of my heatsink after I cleaned both surfaces with ArctiClean 1 + 2, and I noticed that there is a sort of suction when I pull the e4400 back off. That tells me that the surface of the e4400 is pretty damned flat, right?

That lends itself to mean you had a fairly good seal, but that doesn't mean the IHS is flat. The compound spreads and fills any voids left by a non flat IHS.

In all honesty, for a 3GHz OC you don't need to lap. You can if you want to, but it won't help you at all. Your temps will be ~3-5c lower, so lap if you want to. I would say it isn't worth the effort of sanding the proc... it takes some solid effort.

I originally lapped mine because I was going for the highest OC possible and wasn't going to stop short because of temps.

 

[darkspreader]

Ok. I noticed you got your e4300 to 3.3ghz. What are your current temps? I might go passed 3ghz, but I just dont want a ridiculously high temp, lol. I doubt my Infinity will let that happen, however...maybe. :?

 

[SuperFly03]

Ok. I noticed you got your e4300 to 3.3ghz. What are your current temps? I might go passed 3ghz, but I just dont want a ridiculously high temp, lol. I doubt my Infinity will let that happen, however...maybe. :?

Well to get mine to 3375 I was pushing 1.55vcore after having removed the IHS completely from the processor, dropping my temps even further. On top of that I have an Ultra 120 Extreme with a 125CFM receiving ducted cold air form the front of the case.

At that speed load temps using Orthos/Dual Prime/F@H were ~49-51c.

Load temps @ 3150 and 1.45vcore are about 42c.

At stock I idle at 19c and load at 33c.

My temps are way below normal. You can expect to break 62-65c if you push 1.55vcore through your setup, but that is a guess at best. It could be higher or lower, it depends on overall air flow.

For your setup 3Ghz should be perfect. You might have to bump the vcore up to 1.375 or 1.4v and with a silent fan your temps will be solid, probably ~50c depending on what else dumps heat into your case. These are rough estimates, very rough.

 

[jonny_ftm]

19° idle is low. What program are you using: coretemp 0.94, coretemp 0.95 or TAT?
What is your ambient temperature? 19° is some cold for a common room, and a Tjunction under ambiant temperature is not possible. You can reach maybe close to ambiant with a 1.10vcore and 6x200Mhz FSB to see if your temps are well calibrated. Definatly, on air, and with 1.55 vcore it is impossible
Good luck, and give us the details, we all need to know

 

[SuperFly03]

19° idle is low. What program are you using: coretemp 0.94, coretemp 0.95 or TAT?
What is your ambient temperature? 19° is some cold for a common room, and a Tjunction under ambiant temperature is not possible. You can reach maybe close to ambiant with a 1.10vcore and 6x200Mhz FSB to see if your temps are well calibrated. Definatly, on air, and with 1.55 vcore it is impossible
Good luck, and give us the details, we all need to know

At stock I idle at 19c and load at 33c

I said stock is idling at 19c, not 1.55vcore. Stock means 1.3vcore and 200 x 9. This isn't unreasonable, anandtech.com got their Ultra 120 Extreme and X6800 down to 26c and I am using a fan with more than twice the air flow, ducted cold air, and a processors w/o a IHS.

Ambient is 20c.
SpeedFan

 

[jonny_ftm]

I see, I didn't thought your room was around 19°... must be cold there

 

[jay2tall]

To determine if your CPU HIS is flat, get a straigh razor and hold the edge flat on the top. Hot it toward a lamp and see if light comes through. I did this and found my HIS to be concave, meaning the center was lower than the sides. I was getting higher temps on load than I would like when OCing at 3.2GHZ. I lapped mine and droped the temps 5C on load and 1C on idle.

don't lap unless you have to because it voids the warranty. to me my 6 month old CPU was worth it and a new one was $180 or something like that.

 

[SuperFly03]

I see, I didn't thought your room was around 19°... must be cold there

I am a polar bear. 8O

 

[f61]

6 inches off the floor in an A/C room will do it. I've seen my antique Xp3200+ post up at 16c on SD/RS. Ambient at table top about 22c.

Crack a window open in the winter, and 11c on SD/RS. And I wonder why my feet get cold LOL.

f61