Thermal paste

A

Alan

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So I bought some high performance Zalman thermal paste in the hopes of taking a few degrees off my CPU temps. Currently it's @ 45C Idle( CPU is a E6400)

I applied a thin layer to both the heatsink and CPU but the temps are exactly the same as with the old normal paste. I tried other temp monitoring programs but got the same result. So now I'm thinking of applying the paste to the CPU only. Must I clean off both the heatsink and the CPU again and apply the new paste to the CPU or can I just leave the thin layer on the CPU and only clean the heatsink?
 
I personally believe the best way is to clean both surfaces and then to apply a small blob or an "x" in the centre of the cpu. As you apply pressure to the heatsink it should cause the thermal paste to spread evenly over the cpu without creating air bubbles. The right amount to use is enough to cover most of the cpu surface without overflowing on the sides.

Spreading the thermal paste tends to trap air bubbles with a resultant decrease in effectiveness.

Edit: Youtube link to a video illustrating the process:

[ame]http://www.youtube.com/watch?v=EyXLu1Ms-q4[/ame]
 
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This Zalman comes with a brush. Still have the air bubble problems with it too?
 
Using higher quality thermal compound does not necessarily mean you will see a decrease in CPU temp.
 
Not sure to tbh. What do the instructions say?
 
The thicker pastes will not do so well with those methods. They're just too thick to spread out.

I am also under the impression that thermal paste is to be a filler for grooves etc. So if applied correctly there must still be metal to metal contact. In that video I don't see metal to metal (or glass to metal) contact. It's just a solid lump of TIM between glass and cpu.
 
The purpose of thermal compounds is to eliminate the air gaps (air acts as an insulator) between the processor and the heatsink. The thinner the layer that can be used to do this the better. The compound is also a good conductor so metal to metal contact is not required although if metal to metal could be achieved with no air gaps (which is impossible as the surfaces are solid) it would give you optimal heat transfer.
 
Getting some super fine 1000+ grit sand paper and sand down ur heat sink always helps to reduce around 3 degrees. Also you might have a problem with the fan on thermal throtle, so its slowing down to keep ur cpu at 45 degrees, check this in your bios.
 
Why would you want it cooler than 45? Reapplying thermal paste will not necessarily reduce the temps if the old paste was working fine already.

If you want to apply thermal paste try this:

Use sticky tape to mask out a section the same size and at the same location as your processor when attached, on your heatsink.

Apply thermal paste inside the masked off area (where the CPU will sit), and using a flat putty knife, credit card or other flat surface, remove excess paste. You should now be left with a layer of paste which is about the thickness of sticky tape, and in the correct location to be placed on your processor.

Remove the tape, leaving only a thin layer of paste, and attach to your CPU. Note that this method is only useful if your processor is flat, if the layer of paste is too thin, and your CPU is too warped, then it would reduce heat transfer....
 
I think I'll lap my heatsink as well when I finally get it.....Some of the bases on these coolers are horrendous.
 
Ain't that just true. I cleaned the original paste of my H50 today only to find a rough-ish surface. Setting it back down with AS5 applied, then removing it I found only the one half of the CPU was covered. Going to think about lapping the H50 this week, but there are a few complications with how it is built. Then going to order some Coollaboratory liquidmetalpro or crack open a thermometer. Just worried about the screws being aluminium or steel.
 
That stuff is rubbish alan, is it the thermal paste that comes in a bottle with a brush and is very thin, if so it utter rubbish.

Nare in mind it takes 3 or so days before the thermal paste starts working according to them.
 
Yip, probably a BIOS noise reduction setting. Tried Q-Fan on my ASUS board and, ja, it's quiet, but runs at 45C on idle. Check the BIOS.
 
Ok firstly it sounds like you overdid it with the thermal paste. It needs much less than you would think. A small blob or a thin x-shape on the cpu is plenty. Too much paste is actually worse than no paste. All you're doing is covering the grooves, like plaster work, to enable efficient heat convection between the surfaces.

Secondly thermal paste is kind of overrated as a way of eliminating heat - a good aftermarket cooler will do a much better job. If you're using stock cooling the best paste won't make a big difc. Is everything dust-free? How is the airflow in your case? Maybe see if you can direct a chassis fan straight at the heatsink. Is it properly seated on the mobo?

45c idle is a bit too warm but not overly worrying. How is it at high stress? Have you run any tests on it? Try superpi or so for 10 minutes and see how the temps do.
 
killadoob said:
That stuff is rubbish alan, is it the thermal paste that comes in a bottle with a brush and is very thin, if so it utter rubbish.

Nare in mind it takes 3 or so days before the thermal paste starts working according to them.
Click to expand...

It's actually a pretty decent TIM from the various reviews I've read.

Thin does not equal bad, that's a terrible piece of logic. Liquid Pro eg.
 
Thin might actually be even better as it will flow better and allow you scrape most of that excess off and just get it into the grooved bits as intended.

So what is the word with Liquid Pro? I see it for R75 or so, but R50 stupid shipping from Prophecy? Have you guys tried it and what can you say about it? It's the same stuff as in non-mercury thermometers, but at a super-premium price.
 
If the CPU is not under warrenty anymore of if you feel "lucky" you can use 1200 grain waterpaper on the cpu and the cooler surfaces. On my previous system E4300 i got 5-8°C with cheap paste.

You won't believe how uneven the surface of a cpu is.
 
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