Rice or Peanut Butter

[low351]

I have to tell you, there is no substitute for experience.

I've read all the information about how to apply thermal grease. About how you just want it to fill the crevices and not paste it on thick so as to allow less contact between the heat sink (HS) and the processor heat spreader. To the point where contrary to logical assumption less is more. Apply a bead of Arctic Silver, about 1/2 the size of a grain of rice is the recommendation.

Well that worked for me the first time. But I've found that it's dependant on the HS your applying.

Take my OCZ vanquisher for instance. Cheap little HS, $25 without looking for a bargain, a dot of Arctic Silver and voila, 32-36C on an AMD 6400+ X2.

Now it follows that a sturdier HS like the Scythe Ninja in all it's hand cutting glory would require the same treatment right? I mean it has a mirror finish and the Vanq looks like pavement in comparison.

Well my friend, not in my experience. I had to pull it tonight. I was sadly dissapointed that I was getting low 40C with this beast. Where were my low 30s? How could my Vanquisher humilitate such a monster? I checked the seating, okay. I had carefully cleaned the surface of that adhesive imprint from the "Please Remove" sticker. I had dutifully cleaned and prepped both surfaces with ISOPROPYL alcohol. Then I'd put a little wee dot of Arctic.

When I removed it I checked the spread of the Thermal, looked good, just not full coverage. But that's supposed to be right. A circle/oval spread out from the center of the CPU heat spreader.

So rather than swap it for my less than manly, by comparison, Vanq, I decided to try the "peanut butter" method. After another thourough cleaning and a few minutes admiring my geek visage in the mirror finish, I applied a thin coating of Artic Silver all over the CPU heat spreader. Then I carefully grunted, yanked, and pulled the Ninja's stiff AM2 clips into place and checked the seating.

Once I had everything closed up and restarted, low and behold. I was already getting 36C and the Artic still needs 120hours or so and a few cold cycles to cure. Interesting...

[3.0charlie]

I've always used the "peanut butter" method with AS5, and got great temps...

[Prof. Dr. Silver]

Originally Posted by 3.0charlie

I've always used the "peanut butter" method with AS5, and got great temps...

There are only a few ways to put on thermal paste, wether it is the 'rice' method, the 'peanut butter' method (that's a new name for me) or even scraping it out over your chip with a spatula.

There are however many many many many different outcomes of success (or not) It is because of factors such as (but not limited to):

• Type/Quality of Thermal Compound
• Amount of Thermal Compound
• How it's spread-out over the chip
• Heat of CPU
• Mounting of heatsink (how?)
• Type of heatsink
• Use of fan(s)
• Use of case
• Type of case
• Cleanliness of case (no dust)
• Ventilation in case (how is the airflow)
• Ambient temperature in case
• Room Temperature
• Temperature Stability
• Humidity
• Drafts in your house

These are all factors that will give every mount of the heatsink a different outcome in temperatures. If you try to keep outside temps to a constant, you have a better chance of having a more stable temp in your CPU/GPU. If you arrange for great airflow in your case, than that will help getting your temps down. Get the point?

[3.0charlie]

Of course I get the point; but oddly enough even though ALL your factors do apply to my rigs, I always had better temps than most other users with similar hardware. Example? I have a Q6600 @ 3.7GHz, with 1.50V Vcore. The setup is a MCP355 (3/8" tubing), with a MCR220 with 2 Scythe Fs in push config. Full load temp? 51-52C, on all 4 cores.

The AS5 was used with no curing, never following the recommended shutdown periods. It went straight from being assembled to oc'ed to folding 24/7.

[Eldonko]

I used to spread it out but I change HS and waterblocks so often that I switched to the squirt in the middle and squish method simply because it's faster. Temps seem to be about the same to me but I havent really done any in depth analysis.

[Cptn Vortex]

I find the thin strip, for the quadcores, works great every time. Whenever I take the heatsink off I get some Great contact. It kinda helps that I pretty much Lapp every surface, but it is still getting some good contact.

[low351]

Prof. Dr. Silver I made up the "Peanut Butter" moniker to contrast the "grain of rice" comparison that Arctic uses in their instructions. That plus the fact that it's feels sludgy when you spread it with saran wrap on your finger, sort of like PB. I still spread it thin though I didn't paste it on, Since Ideally you want bare metal on metal contact that would be detrimental. Either way though the proof is in the temps measured afterwards.

For the Scythe, since I tested, then pulled and replaced it, the difference is valid. Same ambient temps, same case etc.. the only difference was that the Arctic Silver applied by the rice method was probably cured while the new application *spread* was not. Still I got 40C Idle prior to the re-TIM and 36C immediately after and I expect a drop of about 2 - 3C when the Artic cures.

Obviously I can't compare it to the Vanquisher head on since that was a diffrent case and Motherboard, but loosley considered it was surprising. I'd expect the CM690 to have better airflow than the Elite 330.

Perhaps the Scythe Ninja Rev B. isn't exactly flat, I've heard some HS have concave or rounded surfaces, it looked flat to the naked eye but I did notice some edge contact marks on the copper when I removed it. I chalked that up to the force I had to use to seesaw it into place with it's stiff AM2 clips. They were towards the sides so I don't think they affected the thermal performance.

[Thund3rball]

I'm a spreader, just like my toast. One day I'll try the rice method but I am always confused... is it long grain, basmati, wild, arborio, minute?... Bah! I like the Peanut Butter moniker BTW :)

[Keir]

I've used both, and the big pea method. ( size of pea center of the chip assuming thats like rice but uhh a lil bigger? )

What I dont get is how can yo guys take your heatsinks off and really tell? I mean I can unclip or now unscrew my water block and it'll stay stuck with friction, in order to break it I've gotta move it around it doesnt just pull of nicely, usually in that endeavor I've compeltely screwed myself in being able to tell the distribution. Sometimes it comes off easy.. but am I missing something.

Where's the let the grease release button.. I'm missing it.

[low351]

I got my 2 degrees drop already. I left the computer off for a while to let the TIM cool then tried again and wow 34C instead of 36C Thats now down 6-7 degrees from my previous idle with the rice method. Like I said though I think it varies depending on the HS base, but I'll use spread from now on. In fact I'm debating using up the rest of my AS5 on my board heatsinks, I don't know what ASUS did when they installed them and I'm curious. Plus I have read that AS5 a shelf life or the contents separate so my $15 will be partially used if it goes bad after time. I could put it in the fridge but I'm certain my wife would toss it the minute I forgot it was there.

Keir I was checking the spread by removing the HS before the TIM cured (that's supposed to be about 120hrs including cold cycles for AS5), then of course I had to reapply it and most likely got a different spread pattern from the "rice" grain but I tried to duplicate the way I clamped the HS so hopefully I got close to the same effect. It's kind of guess work in any case, even when it's still maleable it's going to alter when you pull of the HS, the only real indication that you did it right is in the resulting temps.