On 8/29/2021 3:52 PM, Paul wrote:
> Ken Blake wrote:
>
>> Amazon didn't have that one, but I ordered Arctic Silver 5 AS5-3.5G
>> Thermal Paste. That's OK, I hope.
>
> I'm still using the tube of AS3 I got a long time ago :-)
>
> It probably separates a bit after 10 years :-)
>
> Your builder will know about that stuff, and
> calibrating the application of it, so it does
> not ooze out. You put the heatsink on twice.
> The first time, you use less than the amount
> you expect is needed, compress the heatsink into
> it, then take it apart and see how large a coin-shaped
> image it created on the heatsink. Then, wipe it off,
> and apply sufficient to make the material ooze out
> to the edge, without an excess going all over the
> place. Processors with TIM inside are flat. Processors
> with soldered lids are convex. The amount of
> spread of a rice grain of AS, varies with the
> shape of the processor you're working with. I
> think yours is likely flat as a pancake.
>
> If done properly, and you review with an inspection
> mirror (dental mirror), you can make an Oreo cookie
> with the paste, without excess filling showing. You
> should be able to see the white of the AS, but not
> so much of it that it runs all over the place. You
> don't want the joint so dry, you can't see any AS
> present. There should be a definite presence of
> AS showing all around the edge when you inspect.
>
> Whatever you do, don't get that stuff all over
> the LGA1200 contacts.
>
> There is also a two component cleaner available.
> You might keep one of those kits handy, if you
> were a "butter fingers". If you get paste all
> over the place on projects like this, then a
> kit like this would be handy.
>
> https://www.newegg.com/p/pl?d=ACN-60ML

Thanks again for all your advice. I'll print out your instructions and
show them to my builder friend.

--
Ken

Ken Blake <ken@invalidemail.com> wrote:

> Amazon didn't have that one, but I ordered Arctic Silver 5 AS5-3.5G
> Thermal Paste. That's OK, I hope.

https://en.wikipedia.org/wiki/Thermal_paste
"Silver thermal compounds may have a conductivity of 3 to 8 W/(m·K) or
more, and consist of micronized silver particles suspended in a
silicone/ceramic medium. However, metal-based thermal paste can be
electrically conductive and capacitive; if some flows onto the circuits,
it can lead to malfunction and damage."

Artic Silver 5 is not a metal thermal paste despite it has micronized
silver particulate within the emulsion.

http://www.arcticsilver.com/as5.htm
"Not Electrically Conductive:
Arctic Silver 5 was formulated to conduct heat, not electricity.
(While much safer than electrically conductive silver and copper
greases, Arctic Silver 5 should be kept away from electrical traces,
pins, and leads. While it is not electrically conductive, the compound
is very slightly capacitive and could potentially cause problems if it
bridges two close-proximity electrical paths.)"

So, make sure none oozes out when you clamp down the HSF to the CPU.
Spreading it out thinly yourself on the CPU plate before clamping down
the HSF would ensure none oozes out unless, of course, you spread
thickly instead of thinly.

Yep, there are metal-based (aka liquid metal) thermal pastes. They are
hard to apply correctly. They also cannot be used with aluminum HSFs.
Most HSFs employ aluminum, but some use copper heat pipes connected to a
copper base plate, and the fins having no contact are aluminum.

https://www.amazon.com/Thermal-Grizzly-Conductonaut-Grease-Paste/dp/B01A9KIGSI

In fact, I've seen some folks remove the heat plate off the CPU, and
replace the thermal paste under the heat plate. Uffdah! I thought
lapping CPU plate and HSF was inching into overkill. For that, you need
a de-lid tool to remove the heat plate from the CPU case. You remove
the lid on the CPU, remove the existing thermal paste that was between
the silicon and heat plate, apply the metal paste, re-lid the CPU, put
in socket, use highest thermal conductive paste (obviously you don't
want to go cheap at this point), or lap CPU plate and HSF to use metal
paste on them, too, and check how well you did to spread the paste.

https://www.youtube.com/watch?v=kYnUfXl0Gdw

While thermal paste eventually degrades (it dries out, shrinks) and
needs to get replaced, my understanding of the metal paste is it far
more fragile. Higher thermal conductance with lower reliability.

On 8/29/2021 5:16 PM, VanguardLH wrote:

Thanks again.

> Ken Blake <ken@invalidemail.com> wrote:
>
>> Amazon didn't have that one, but I ordered Arctic Silver 5 AS5-3.5G
>> Thermal Paste. That's OK, I hope.
>
> https://en.wikipedia.org/wiki/Thermal_paste
> "Silver thermal compounds may have a conductivity of 3 to 8 W/(m·K) or
> more, and consist of micronized silver particles suspended in a
> silicone/ceramic medium. However, metal-based thermal paste can be
> electrically conductive and capacitive; if some flows onto the circuits,
> it can lead to malfunction and damage."
>
> Artic Silver 5 is not a metal thermal paste despite it has micronized
> silver particulate within the emulsion.
>
> http://www.arcticsilver.com/as5.htm
> "Not Electrically Conductive:
> Arctic Silver 5 was formulated to conduct heat, not electricity.
> (While much safer than electrically conductive silver and copper
> greases, Arctic Silver 5 should be kept away from electrical traces,
> pins, and leads. While it is not electrically conductive, the compound
> is very slightly capacitive and could potentially cause problems if it
> bridges two close-proximity electrical paths.)"
>
> So, make sure none oozes out when you clamp down the HSF to the CPU.
> Spreading it out thinly yourself on the CPU plate before clamping down
> the HSF would ensure none oozes out unless, of course, you spread
> thickly instead of thinly.
>
> Yep, there are metal-based (aka liquid metal) thermal pastes. They are
> hard to apply correctly. They also cannot be used with aluminum HSFs.
> Most HSFs employ aluminum, but some use copper heat pipes connected to a
> copper base plate, and the fins having no contact are aluminum.
>
> https://www.amazon.com/Thermal-Grizzly-Conductonaut-Grease-Paste/dp/B01A9KIGSI
>
> In fact, I've seen some folks remove the heat plate off the CPU, and
> replace the thermal paste under the heat plate. Uffdah! I thought
> lapping CPU plate and HSF was inching into overkill. For that, you need
> a de-lid tool to remove the heat plate from the CPU case. You remove
> the lid on the CPU, remove the existing thermal paste that was between
> the silicon and heat plate, apply the metal paste, re-lid the CPU, put
> in socket, use highest thermal conductive paste (obviously you don't
> want to go cheap at this point), or lap CPU plate and HSF to use metal
> paste on them, too, and check how well you did to spread the paste.
>
> https://www.youtube.com/watch?v=kYnUfXl0Gdw
>
> While thermal paste eventually degrades (it dries out, shrinks) and
> needs to get replaced, my understanding of the metal paste is it far
> more fragile. Higher thermal conductance with lower reliability.
>

--
Ken