you need the arctic silver.
However, the compound should not come anywhere near the bridges. you should just put a small amount on the rectangle-shaped, elevated core in the middle of the chip.
Or at least this is the way I was told to do it.
Do people put this stuff all over the chip?
You put the arctic silver all over the chip, even covering the bridges? Not just on the core?
I heard that this actually insulates the chip and causes temps to rise.
On the P3's, Tbird's, Duron's, etc. you only put a small amount on the core in the center of the chip. You want a relatively thin layer, a small gob and then spread it. Some people say to smear it evenly over the surface of the core with wooden popsicle stick. Then you put the heatsink on carefully, and wiggle it a little bit to work out any airbubbles. All you want it to do is fill in all the little spaces between the CPU and Heatsink. Too much is actually a bad thing.
To get an idea of how much you actually need, take a look at a heatsink that has the crappy thermal tape on it, that has been running in a system for a couple days. The actual layer that remains where the core sits is less than paper thin, with all the stuff around it intact. It's like a little square burned into the tape.
You're suppost to only put a small layer (like paper thin), not a huge layer of goop.
But it's not over the WHOLE chip. Just around the center.<P ID="edit"><FONT SIZE=-1><EM>Edited by Grizely1 on 12/14/00 11:51 AM.</EM></FONT></P>
You only put the thermal stuff on the small chip on the center, not all over the processor! this stuff is meant to be applied in very small amounts, to even out the surfaces which make contact. Even while the surface looks all smooth, there are very small gaps and stuff, which you can't really see well or even feel. The thermal compound will fill these gaps and therefore make better contact and transfer more heat. But this only works if the layer of thermal compound is really thin. A very thick layer will result in lower heat transfer, and if it touches the bridges, well, i think that could cause some serious damage (don't know for sure).