davy wrote:
> Speaking from experience I have seen TV's and video's where the failure
> of power transistors and FETs in the switchmode supply due to the
> actual white stuff from drying out... infact one manufacturers
> modification was to remove this white stuff and replace it with their
> recommendations (usually their own stuff costing that little bit more)..
> I literally had to scrub the old white stuff off from Tv's and video's
> less than 12 months old. When things are under warrenty you have to
> repair them to the manufacturers specs or they don't wanna know should
> they have to have it back.
>
> Common wheel bearing grease.. well thats new just remember there's
> wheel grease and wheel grease but you don't say what brand it is...


"Coastal Industrial Moly EP Grease"



>
> but grease also forms a film and why don't all manufacturers use it...
> there's a heck a lot if it about, tonnes of it..?


Dunno. But I'm NOT the only one using it.


>
> This heat sink stuff contains oxides which comes in all proportions as
> to brand... you gotta admit that the white stuff is far more thicker
> than the stuff you see on CPUs and takes more pressure to spread.
>
> All we are interested in is filling the gaps the mating surface with a
> heat conducting agent such as a metal oxide.
>
> Davy
>


Having smooth mating surfaces and reasonable pressure on the CPU and
heatsink will help reduce the amount of "fill" necessary. Applying the
material correctly should result in such a thin layer. Its very
important to have a smooth material that will flow out, conduct the heat
through that very thin later, and not break down are the important
characteristics. These are the exact characteristics of the wheel
bearing grease noted above.

From what I've observed trying different heat conducting materials,
there really isn't that much performance difference between them.

But your machine is not my nickel, so you need to choose your own poison.