black patch/thermal compound on P4

Just opened up the Intel P4 2.8c retail box. (Opening the package, the
CPU flew out and landed on the heat sink) Hope it's ok. Anyway, its
got this black patch on the bottom of the heat sink, is that the
thermal compound or do I remove that?

Is that 'patch' reusable? Instructions make no mention of it.

On 28 Jul 2004 18:28:17 -0700, (jf) wrote:

Just opened up the Intel P4 2.8c retail box. (Opening the package, the
CPU flew out and landed on the heat sink) Hope it's ok. Anyway, its
got this black patch on the bottom of the heat sink, is that the
thermal compound or do I remove that?

Is that 'patch' reusable? Instructions make no mention of it.

yes it is phase-change thermal material, you don't want or need
to remove it, necessarily.

Being phase-change type, if/when you remove the heatsink later
after running system, you must then clean that stuff off
(petroleum solvent works best) and apply heatsink grease
instead... it is not reusable.

Someone who plans to remove heatsink soon or wants a couple
degrees cooler CPU might want to go ahead and clean off that
original TIM (thermal interface material) using petroleum solvent
after scraping most off with a credit card (object softer than
heatsink metal so it's not scratched). However, it theory it
might void the CPU warranty to remove it, but we're drifting into
a grey area here, as Intel can't really expect someone to never
retry CPU after removing heatsink that first time.