Temperature Issues AFTER Lapping - Ideas?

[htwingnut]

Ok, so I get my new E6850 chip to replace my E6600. Plop it in, and temperatures seem to be a little higher than I was used to with the E6600. I used TAT to test (note that the approx 15C correction was added to temp results). With the E6600 I was running about 55C with TAT after 20 minutes. With my E6850 I was running approx 62C after 20 minutes. Not terrible, but not desirable.

So after removing the HSF from the CPU I noticed that little if any AS5 ws touching the heatsink. After doing some forum searching, I found that concave IHS's are none to uncommon, so I decided to lap the IHS and the heatsink since results seemed promising, so went ahead and lapped them. Well, the IHS looked nice and smooth, but the heatsink lapping didn't go so great, as the surface was much more dull than before I started.

I reaassembled the system and while the thermal grease was distributed evenly across the surface, indicating a nice flat surface between the chip and the heatsink, my TAT temperatures were running into 70C+ range!

So I decided to replace my HSF with a new one thinking I might have done more damage than good by lapping it, as this is a quality Zalman HSF (7000). Well, temps are now running about 70C still.

Weird thing is that when I first powered on my PC after using the new heatsink, the idle temps were about 25C. After a couple runs with TAT or Orthos, and cooling down all the way, idle temps are now at about 35C. Ambient room temp is about 20C.

I use only 99.953% isopropyl alcohol for general cleanpup and use the ArtiClean surface purifier from ArcticSilver prior to applying the paste.

Any thoughts or suggestions?

 

[knowsitall]

when you lapped.. what did u lap on? did u tape the sandpaper to glass and sand the cpu that way. soundst o me u dont know how to install heatsinks, or u made ur ihs worse, seeing u screwed up ur other one. go get a razor blade and put it to ur ihs and see if it looks flat/str8.

 

[htwingnut]

I'll assume English is not your native tongue considering your poor grammar/spelling and somewhat insulting tone. I know how to install heatsinks. I've handled computers and PC components for twenty years. Just never took it to more extreme measures before like lapping or water cooling.

I got the kit from easypckits.com, yes, taped down the sandpaper to glass and the glass to a mirror, used dish soap with water, blotted frequently, and took my time. The IHS is as flat as it can possibly be, as measured by a razor blade. I should have taken a picture of it before as there was a significant gap between the razor blade and the IHS. Now there's no gap.

The Zalman cooler was just too difficult to handle steadily considering it has all the small fins around it all the way down to the base. My biggest issue was that the IHS was not flat.

 

[knowsitall]

I'll assume English is not your native tongue considering your poor grammar/spelling and somewhat insulting tone. I know how to install heatsinks. I've handled computers and PC components for twenty years. Just never took it to more extreme measures before like lapping or water cooling.

I got the kit from easypckits.com, yes, taped down the sandpaper to glass and the glass to a mirror, used dish soap with water, blotted frequently, and took my time. The IHS is as flat as it can possibly be, as measured by a razor blade. I should have taken a picture of it before as there was a significant gap between the razor blade and the IHS. Now there's no gap.

The Zalman cooler was just too difficult to handle steadily considering it has all the small fins around it all the way down to the base. My biggest issue was that the IHS was not flat.

english is my first language. I just type like a slob online since i m not concerned with my grammer while online. I was not insulting you only trying to help you. So sorry you absorbed my message in that way. I m only trying to figure out whats going on here. What program are you using to measure your temps? Download Speedfan or Coretemp and tell me what temps you are getting with those programs. What Voltage is your cpu set to in the bios? if it is anything over 1.35V you might want to lower it to 1.35. Please dont insult me, i am trying to help you, and i seem to be the only one helping you. You are using the 7700 heatsink? i dont believe that is such a good cooler. I hear people usually got with the 9500 or 9700. But 70 is still even for a 7700 i would guess. I dont know, check your voltages/ download core temp and tell me your reading. Is your cpu overclocked right now?

 

[htwingnut]

Sorry, just things like "you don't know how to install heatsinks..." or "you screwed up the other one..." sounded a little rude. Let's consider it a misunderstanding. <handshake>

No overclocking; using SmartFan, TAT, CoreTemp to monitor temps. CPU-Z shows voltage is running approx. 1.2v. That's why I'm boggled.

I had overtemp issues with my E6600 when trying to overclock, but realized that the "AUTO" voltage regulation on the BIOS was bumping it up to 1.40V+, so set it to 1.30V and it ran like a charm.

Anyhow, I just can't figure it out. I'm not overly concerned as temps are within spec, but is always nice to drop a few degrees before attempting any overclocking.

I am running in a small form factor PC: Silverstone SG01, and it can't accommodate a very big HSF. The 7700 is a few mm to wide, already tried it. Either way the 7000 has excellent reviews, and performed well with my E6600. I don't feel that is the issue.

Maybe lapping the IHS was just a bad idea, but considering the distribution of the thermal grease, it seemed warranted.

Additionally, I am assuming the +15C temperature differential on two basis: (1) The thread here at Tom's hardware on overclocking your Core 2 Duo and (2) Comparing idle temps in BIOS and then using SpeedFan results in an approx 15C differential (Same with TAT and CoreTemp)

 

[Matt4109]

It could be that you used the wrong amount of arctic silver. You don't need near as much if you have lapped it. If they were both extremely flat you night not have needed any at all. Arctic silver is meant to fill in those convex/concave spaces and if you don't have any spaces then the ac is only for those microscopic spaces.

 

[sunderlion]

I recently lapped my E6600 (down to the copper) and had a similar problem with increased temperature (~+5 C at load). It turned out that the bottom of my heat-sink was FAR from flat, and by flattening my CPU IHS I actually got less contact with the heat sink than before. However, after I lapped the heat sink (also, down to the copper) there was a DRAMATIC decrease in CPU temperature (on the order of 10 degC under full load).

My advice would be to remove and Lapp your heat sink. I suspect that would solve everything =)