Rise in temps with a lapped heatsink?

[Xstatic]

Ok here is the deal, I'll start from the begining. I got my 165 a few months ago and all was well. Temps were really good. Stock Heatsink and fan got me up to 2.6 fully stable and 2.7 partialy. Temps we about 27c idle and about 42c load if I remember correctly without checking my logs. This is with th stock fan on it. So I decided to put a new fan on it to see what I could get. I put a 120mm smart fan on it with a 80-120 adapter. Temps went down. At night with the window open it would turn the fan off cause it would get below 25c and dip as low as 22c. Now I dont have a temp probe the check it but it was very very cool to the touch and the air being blown around the heatsink and fan when it was just slightly above 25c was the coolest I have felt in a case. And the load was in the high 30's some times 40c if the room temp was a little higher.

Now here is where it gets odd atleast for me. I bought a AC Freezer 64 pro for like 15 on sale and wanted to try it out. It a big thing with a bunch of heat pipes. So I lapped the sink before I put it on and got a pretty good finish on it(atleast for me being my first time) and put it on and tested it out. First thing I noticed was the temps jumped about 10c. So at first I was like well thats odd but maybe its the as5 and it needs to settle in and the temnps will drop. But then after a day or 2 I knew something was up as i have never seen a big drop in temps with as5 settleing in after a week or 2. Maybe a 2-3 degree drop, and that is about it. So I reseated it to make sure all was well and still the same temps. I decided to lapp my stock heasink while I was waiting for the temps to drop after putting the new sink on the first time. I got a better finish on the stock HS then I did on the freezer. Made sure no wobbles in it with the graph thing I d/led, and tossed it on and made sure it was seated well. Still the same temps 38c idle and high 40's sometime 50c. This way way hotter than it use to be. I didnt damage the core or the board as I was carefull to remove and put it back in. I've done this enough times to know how carefull to be. But I can't understand why I would get this jump in temps like this. Its been week and a half since I put the stock lapped HS back in so there has been enough time for the as5 to settle in. I got maybe a 1-2c drop at idle but that maybe because of room temps.

I have the ac on and its rather cool in the room. The coolest I've seen it at idle now is 34-35 and that is when its chilly in the room. Any suggestions or reason why this would be? Lapping is suppose to drop temps. Even if its only a degree or 2. But now its jumping up 10 or more? Im so frustrated and need help.

Thanks guys.

 

[Flip-Mode]

Well it just might be that the mobo sensor is wrong, that would be my guess.
Check your OC, if its stable then leave it be and the temp probe is off.
If you can raise your OC then the temp probe is wrong 100%

 

[tommcd64]

Make sure you didn't create any convex or concave curves on the heatsink when you lapped it.

 

[muddocktor]

What kind of surface did you use to lap on and what grit wet-or-dry sandpapger did you use for your lap job?

 

[Xstatic]

I used wet-dry Sandpaper and used 400 then used 800 then 1000 then 1500.

I used a kitchen table glass surface. Very flat. Was going to use the marble counter top but I didn't want to stand up the whole time.

And I used the graph pic that you can d/l to put up to the HS to see if it is flat or not. And it had no ripples in it.

 

[Xstatic]

Should I of used somethig else? Or done it differently?

Anyone else got any ideas as to why this is happening?

 

[archilochus]

It's possible that you changed the clamp pressure on the chip by removing metal from the HSs base while lapping..
Look for ways to increase clamp pressure. (A shim between base and clip..)
In the future, check the HSs base with your graph before lapping...

*See thread* http://www.ocforums.com/showthread.php?t=462216

 

[tommcd64]

I use a piece of glass that I got from a lapping kit. Clean your heatsink and your cpu. Put a small rice grain size amount of thermal past on the center of the cpu. Then install the heatsink. Then remove the heatsink and see if there are any places on the heatsink where there is not thermal paste. If there is, then the lapping is uneven.

 

[Xstatic]

I dont like the glass from the glass kits as they are too small and can be akward. I use the table as it is bigger and allows you to put the SP anywhere and be comfortable. I might haveta look to see if there are any places where the paste isnt getting and see if there is any spots where its not touching.

I'm not totaly sure how to put a shim in there. I dont want to mess anything up.

 

[bolillo_loco]

How long does it take to do a lap job? A mirror finish lap job that is.

 

[XxNightfirexX]

How long does it take to do a lap job? A mirror finish lap job that is.

That depends on how bad the surface is to start with. With my Freezer Pro, it took about an hour, but the finish was extrememly bad. I also started out with a finer grit paper than I would have liked to use for the marks that were in the surface when I started (I was too lazy to run to the parts store again), so it took a very long time to get through the worst of the machining marks. I'm just glad I was taking off the stock TIM to use AS5, if I hadn't been doing that, I would have never seen how bad the surface was.

 

[Xstatic]

Ok I'm still stumped on this. I can not get the temps to go back to normal. I'm wondering if something happened when I canged the sinks and lapped them. Maybe I bumped something or maybe its not getting a good contact now. But I can't figure out what would of got bumped.

And as far as how long it takes to lap a sink.... It took me about a hour to do mine.

 

[orion456]

Do you know if the CPU voltage is the same as it was before? Sometimes the BIOS doesn't give the same voltage every time when set on auto, and voltage makes a huge difference in temperatures.

 

[Susquehannock]

Is the thermal paste applied correctly? Too thick a layer will act as an insulator & raise temps.
The more smooth & flat the surface the less TIM you need.

On mine I apply just a light transparent haze - to both surfaces. I use Shin Etsu X23-7783D by the way.

>>>>>>>
I'm not totaly sure how to put a shim in there. I dont want to mess anything up.

Shim??
That would be a bad idea.

 

[twitchee2]

What i would sugest, is take a sharpy for something, and put some marks on the bottom. Then if you have a piece of glass or a sanding block (something flat) to use as a sanding block, that works the best for me. Then start sanding away under a water faucet. When the sharpy gets sanded off, you will be able to tell if it concave or convex by the way the sharpy is wareing off. try that out.

 

[Xstatic]

I have already done the lapping and it was done correctly. Its not concave or anything. Its flat.

And as far as volts I had it at 2.8g but didnt like the temps after the lapping and droped the volts and the oc to 2.7g. Its still higher then before the lap.

And for the TIM I said this already in a previous I only use a half to full grain of rice when applying TIM. I never put more than that and I know what more will do.

My main question is since its a 939 and the temp probe on board is under the socket(correct) there is no way of bumping it right? I didnt hit anything that I know of or atleast anything ovbious. So could it be that before I just got a really really lucky seat and now I'm just getting unlucky? I mean temp in the mid 30's at 1.5 v at 2.7 and about the same for 2.8 at 1.55, maybe a degree or 2 higher. But this chip use to run really cool. I mean mid to high 20's idle and upper 30's maybe 40 load ( useing prime, cpu-burn, stresscpu) and ran like that all the time. Depending if it was a cool night and I had the window open it would atcually turn the fan off because it would drop below 25c. Now with the window open and a window open on a cool night(40f the last couple nights) its been dropping down to about 31-33 or so. One thing I did notice is when I cneck my temp now useing ITE smart guardian it shows a fast fluxuation in temps. As in like 1 second intervals whereas it use to be like 3 second intervals. Maybe something to this? I check smart guardin options and seen no options for how fast it checks and reports the temps. So that has not changed. And it fluxuates in temps from like 35 to 37 then to 36 then 38 then 36 then 37 then 35 ect...it bounces around alot. Before it would stay at like 28 for a few seconds like maybe 5 then go up or down 1 degree. and do the same. It was slow at displaying the new temps kinda like the chip wasnt changeing temps much very fast. I haven't reinstalled the ITE SG or anything since then. I'm lost and just want to get back to normal temps.

Sorry for any grammar errors or any typo's as I typed this as fast as I could and didnt even try to type correctly. Long day at work.

 

[UglyChild]

How well did you clean the CPU and the Heatsink after you lapped it? Its very important to get it as clean as possible, because that can make a day and night diffrence. Use sopropyl Alcohol. I prefer to use this as it evaporates, unlike polish, because you don't want a layer of anything depleting your heatsink's performance.


http://www.overclockers.com/tips1015/

You may if you wish use a higher grit than 600 to finish with - some people even go to a 2000 grit (so fine it would only take the shine and not the paint off a Mercedes body work). However, it isn't necessary to have it so smooth - 600 grit will give a smooth enough surface and going to a higher grit may make it shinier, but you certainly won't get a performance gain (this has been debated many times).

 

[Xstatic]

I used I think 90 something % Isopropyl. It was clean. And I used 400, 800, 1000 and finaly 1500 I believe. Didnt see any need to get it any more of a mirror finish.

 

[UglyChild]

OK.

Do this if you can for us; take off the heatsink and take a picture of both the CPU and the Heatsink while there is still TIM on them, so we can see how good of a contact two surfaces make.

Thx