Lapped CPU + Heatsink, TIM question

[iDont]

Hello,

I finished lapping my heatsink and the CPU itself yesterday, I used up to 800 GRIT sandpaper on the heatsink and up to 1200 GRIT sandpaper on the CPU.

Now I've read a LOT of different techniques to apply TIM and tried several of them myself, but I can't seem to find the right way of applying it to my lapped CPU.

I have been told that I need to:
- apply a very small amount on the center of the CPU
- spread a thin layer out with a credit card over the whole heatsink/cpu
- apply a line of TIM on the CPU/heatsink

Now I'm asking the forum members who got their heatsink + cpu lapped how they have applied their TIM and how much of it (well, suggestions from everyone are welcome ).

Thanks in advance,
-iDont

ps. I'm currently using my pc with a line of TIM applied to the CPU and it's running about 1 degree cooler than normal, but I guess that has to do with the fact that it was about 10:00am when I checked the temps + the TIM needs to settle

edit: I'm running an AMD Athlon X2 4800+ OC'd to 3GHz @ 1,275V (plenty of headroom) combined with an ThermalTake Ruby orb. I know, it's not the best cooler, currently saving money for a better one.

 

[aCid888*]

I apply a thin layer, really thin!

I find it works quite well

 

[CrAsHnBuRnXp]

It depends with me. Right now with my setup, I have a a layer going across my CPU. I put a decent size in the center of teh CPU and spread it out with my finger while wearing a latex glove. I didnt go in circles but instead rubbed the grease on going from center to left until that side was good. Then center to right until it was coated. I end up using a bit more that way but my temps dont lie. I get anywhere from 18-25*C idle at 3.8GHz 24/7.

 

[panchoman]

put an extremely extremely small drop of tim on the center of your cpu and let the heatsink squash it.. remember, its so freaking close contact that you hardly need any TIM at all.

 

[Eternal]

I usually apply mine just like u said, a small amount on the middle of the cpu, like the size of a grain of rice. Then go back n forth with a credit card until its reeeaaalllyyy thin.

The thinner the faster the heat transfer form the CPU to the cooler.

 

[iDont]

I thank you all for your replies.

When I tried to apply an even thin layer all across the CPU, the temps skyrocketed to about 60 degrees with Prime95. I guess I've used way to little, as I don't think the temps will lower that much while the TIM settles. I only used that much so the metal looks a big vague, yet still reflects objects if there is enough light in the room.

I'll try grain-size drop in the middle in a few days, first I want to let the current amount settle so I can make a good comparisment. Maybe I'll try the 'spread-out' method again later (with more TIM), depends on how the current setups work out.

Any further suggestions are greatly appreciated.

-iDont

 

[Steevo]

A rice grain sized drop in the middle works well, as the CPU heats it will be pushed out the sides. No need to try and settle it yourself as others are saying, the idea of the phase change compund is to allow for settling.

 

[iDont]

One last question: if I use a grain size drop on my lapped setup, wouldn't the TIM form an isolating layer, or is this over-exaggarated (or does this only apply to the guys who use up to 2000 GRIT)?

Thanks in advance
-iDont

 

[Steevo]

It will move, again the idea of a phase change compound is that it become less viscous when heat is applied or present. To truly get mine to set on fast I on purposely bumped the volts to the CPU and slowed the fan, plus a little wiggle and it squished out in a few minutes. This is a dangerous way to do it, but it worked for me as mine wouldn't settle.