Is lapping a core i7 worth it?

[Metallica]

Their engineers are smart; they can figure out if you killed a CPU from overclocking. Not to mention it's not exactly ethical to RMA a CPU killed by OC'ing.

If you RMA a dead CPU, I'm pretty sure they can't tell if it was from OCing. And if you RMA if for another reason other than being dead, I still don't think they pay that much attention, as long as it works.

 

[Ben333]

They don't know weather or not you overclocked it, nor would the waste the time or money to find out if you did. I'd guess they maybe pop RMA'd chips in a computer to test them, or they go directly into the trash/recycling. (after inspecting them for physical damage) Lapping however will definitely void your warranty. Also, I don't think saying that anyone NEEDS to lap their CPU is right if it is slightly bowed one way or another. If it is to the point it won't run and has horrible temps with a proper heatsink mounted on it I'd say that's grounds to RMA it but otherwise thermal paste does the job of filling the non contact areas. If you don't care about your warrenty and want some lower temperatures then lapping is an easy way to do it. Make sure its flat though, you can lap it and have it look great but you must lap it evenly - be sure to use equal force so you don't round the edges or lap it at a slant. I don't know why lapping guides suggest starting with such high grits, I usually start at 100 or 200 and then 400, higher if I have the sand paper on hand to finish with.

 

[downer]

I start at 150 grit, then move to 400, and finish at 600. I don't know how people can start at 400. It takes ages to lap starting at 150.

 

[Voidn]

Yes, it does. It seems that gentleman gained about 10c when he lapped.

Impressive.... but I'm scurd. I'm going to practice on a true and maybe some old hardware first.

 

[GMdoubleG]

These are two videos I've found of a guy lapping his E8400 using 600, 800, 1000, 1500 and 2000 grit sand paper. Am I wrong to think that his way is safer because of the exactness of how he uses each grit and there isn't much guessing or "feeling"?

 

[Albaholic]

You guys have some serious...uh parts of the male body....to do this. I couldn't consider doing it even if it resulted in sub ambient temps. In my mind I may as well be taking sandpaper to two crisp 100 dollar bills. I have no problem building watercooled rigs or messing with computers but my mod skills are really off. I know if I tried this, I would be out either a CPU or a finger.

It would take some serious talent to lose a finger while lapping with just plain ol' sandpaper

These are two videos I've found of a guy lapping his E8400 using 600, 800, 1000, 1500 and 2000 grit sand paper. Am I wrong to think that his way is safer because of the exactness of how he uses each grit and there isn't much guessing or "feeling"?

It's really not that hard & you don't have to go all the way up to 2000 grit. That mirror finish isnt going to net you much improvement. If you're really that worried. Pick up some free old hardware off CL to practice

 

[Spawn-Inc]

i started off with old hardware and then moved to my celeron 420, then to my q6600. it's easy, just time consuming. i taped off the back of the chip and used Styrofoam to make it easier as well.

q6600 thread

celeron thread

 

[orion456]

Is temperature really a limiting variable for i7's? It seems frequency and voltage are the main problem. Especially water cooling, the i7 stays at reasonable temps before it stops booting.

If so, then lapping won't produce much improvement in OC even if you get a good temperature drop; which at best would be around 5c, and worst might be nothing.

Lapping doesn't seem worth the bother and loss in CPU value.

 

[GMdoubleG]

I haven't heard anything about the i7 having shut down problems due to high temps but I'd like to keep the temps as low as possible for ease of mind.

Now that everyone has convinced me that I should lap my i7, how long should I run/test the CPU to make sure that it won't fail on me from faulty production? Is having to RMA a CPU very common?

 

[Voidn]

Is temperature really a limiting variable for i7's? It seems frequency and voltage are the main problem. Especially water cooling, the i7 stays at reasonable temps before it stops booting.

If so, then lapping won't produce much improvement in OC even if you get a good temperature drop; which at best would be around 5c, and worst might be nothing.

Lapping doesn't seem worth the bother and loss in CPU value.

Some of the D0's are high temp low vcore, like mine, so every degree counts, 5-10c drop in temp would mean I could run 4.3 or 4.4 ghz 24/7 at 1.4vcore which is bordering on the unsafe but I see people going higher all the time. Or I could stay at 4.2 and never go over 70c, which would make me all warm and fuzzy inside .

Though it is probably a good idea to find your chips limits before lapping, to see if 5c will do you any good. If you already have good temps but it needs too much vcore/qpi to clock higher then lapping wouldn't matter.

 

[GMdoubleG]

My Apogee GTZ has a few stains on the surface that makes contact with the CPU so I want to lap it. Should I use the same procedure as lapping the CPU? Or should I try to take as little off as possible?

 

[Conumdrum]

GM, I'd not lap it. The spots are wayyy less than 1/1000 thick. Ketchup and a good scrub with a pad that has the plastic brillo on the bottom is enuff. The kind of pad that billions buy at the grocery store.

Don't worry, it's not going to make a diff in temps.

 

[GMdoubleG]

Ok, I've tried using ketchup and the pic above is after leaving ketchup on the copper for about 5 min. At the moment, I am trying to diagnose why my Q9450 temps are so lousy before I go to the i7. This is just another thing I wanted to rule out.

 

[Albaholic]

What kind of temps are you getting?

 

[GMdoubleG]

In mid-day, with ambient temps below 80*F, load temps at stock are around 52*C and load temps OCed to 3.2Ghz (400FSB) hits highs of 60*C. As in my sig, I have a dedicated loop to the Q9450 with a XSPC 360RX rad. I am now thinking that there isn't enough air being passed through my rad. The pic below shows that I have two MCP655, some hosing, and lots of wires that might be inhibiting air to flow though.

 

[GMdoubleG]

I have three Yate Loon fans at 1650 RPM on the XSPC 360RX.

 

[Spawn-Inc]

leave the ketchup on the block for 30 minutes and it should be gone, did for me.

 

[hitokiri_808]

Before lapping, do a razor test - put a razor's edge across the CPU from multiple angles and hold it up to a light. If you see light under the razor, the IHS is not flat and you'd most likely benefit from a good lapping. If it's flat to begin with, there will still be a benefit, but potentially not significant enough for the trouble (meaning 1-2c as opposed to 4-5c), unless of course you want every single degree you can get and would be satisfied with a relatively small drop.

+1. Lap both the hs and ihs for maximum contact.

 

[GMdoubleG]

Will leaving ketchup on the GTZ for 30 min cause any unevenness?

 

[Spawn-Inc]

it won't mess with the flatness or anything, it doesn't work that fast. try 15 min first if you worried about that. then go for more if it's not removed. i personally went out and forgot about my dtek in the ketchup for a good 2 hours. still have great temps.