"phase change pad"???

[JesseKnows]

What is the meaning of these words? I saw it applied to the pad on Intel stock HS. I thought the pad was there for mechanical cushioning and heat transfer (or lack thereof). What's with the phase stuff?

JesseKnows

 

[Mikewarrior2]

Which P3 retail did you get? AFAIK, the P3s retail sinks don't come with Phase-Change pads..

That being said, PCTC (phase change pads on Socket-A heatsinks) are fairly foolproof, and offer okay performance.


Mike

 

[JesseKnows]

If you perform a google search for 109X7612H1036, which is the part number on the fan, you get to this page:http://millisec.safeshopper.com/51/369.htm?188 (look at the cached version, the site wasn't there when I tried). It shows the Intel retail heat sink and mentions the phase change pad.

So what is it, anyway?

JesseKnows

 

[JesseKnows]

Never mind, did my own search. It is an elastomer which melts at about 40 degrees C and then conducts heat. Sort of like applying the heat transfer grease in a solid state. Supposedly doesn't dry out either.

Since I took it off for lapping already, I will live with the RS grease

JesseKnows

 

[bacillus]

could be wrong here but once the temp of the pad exceeds a threshold,usually something like 40C,pad becomes more elastic & mirrors more to the shape of the cpu core leading to better & more optimal contact for heat transferance!

 

[thermite88]

JesseKnows,

The correct Millisec Page.

The phase change pad is a thermal interface material that AMD specified for their Socket A CPU's.

<< Note: The phase-change thermal compound is very important to the efficiency and success of the heatsink. The compound must be applied evenly to the surface of the heatsink so it can (basically) melt and fill any microscopic voids in the surfaces of the processor and heatsink with a thermally conductive material. >>



<< Caution: If you have never installed a heat sink with this type of phase-change thermal material, we suggest that you not remove this film until after you have practiced installing the heatsink and mounting the clips on the socket. It may take a few trials until you are familiar with the procedure. >>

The Intel heatsink never used a phase change pad because the Intel CPU does not generate enough heat to &quot;melt&quot; the pad.

You can find more information at the AMD site.

I don't know where Millisec got the idea of phase change pad on Intel OEM heatsink. Last year, Millisec advertised a Thermaltake heatsink for the AMD Duron/Thunderbird CPU, which turned out to be not approved for Socket A use by Thermaltake. Millisec tried to lay the blame on Thermaltake and stopped selling Thermaltake heatsinks shortly afterwards.

 

[JesseKnows]

So, what was the stuff I scraped off the Intel HS, if not a PCP? It scraped off easily, with little self adhesion - I was pushing with some stiff plastic (so as not to scratch the aluminium) and it came off where I pushed and separated from the rest of the pad matter. It almost crumbled, but was just a bit too liquidy to really go into crumbs. Sorry for the poor explanation

JesseKnows

 

[ApacheXMD]

that was probably a graphite thermal pad. afaik, it doesn't change phases. was it grey?

-patchy

 

[thermite88]

The white stuff on the Intel retail heat sink is better quality silicon based thermal paste. Intel used to use Dow Corning 340 thermal Grease, as were most of the major HSF manufacturers. It will dry out over time, but are better quality than the Radio Shack stuff.

 

[DolphinJay]

I've always read that your supposed to scrape thermal pads off any of the heatsinks and apply better thermal compound.

 

[JesseKnows]

I was just musing how much effort is wasted in the world by these kinds of manuvers: Intel puts inferior pads on the HSs to reduce the likelihood of successful overclocking. This raises the production costs, and prices, of the retail product. Then we scrape it off and apply a different substance.

BTW, even if true, this would only apply to CPU manufacturers' products. Any other HSF manufacturer would have no motive to put something that's worse than RS paste on the HS, they should either be at least as good as RS, or put nothing and tell the buyer to use their own.

Or is the alternative _nothing_, and the OEM pad better than nothing?

JesseKnows