# is cpu thermal grease electrically conductive



## philheckler (Apr 14, 2005)

Hi,

Got a smear of thermal grease on some components near the cpu whilst uninstalling my old mobo - i'm hoping to sell it and the cpu - thermal grease looks mettalic - is there a chnce this coluld cause a short / leakage issues to the board if not cleaned off ?

thanks

Phil


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## UncleMacro (Jan 26, 2005)

Most heatsink grease is non-conductive. But if you're using one of the silver based greases, then you may have a problem. Silver grease is only a little conductive so it's unlikely to cause a short. But it's also a little capacitive. That means that it slows down high speed signals and that can be a serious problem. People hurt their video cards all the time while adding after-market heatsinks by getting the silver based grease on their video RAM chips or GPU. Those RAM chips communicate at very high speeds and the extra capacitance can slow the data enough to cause artifacts. Most motherboard lines aren't going as fast but you definitely want to keep the silver grease away from them anyway. If it's not silver based grease then it shouldn't make any difference because its conductivity and capacitance is very low.

I've always avoided silver greases like the plague. I used to design hardware and if I had ever suggested using a conductive/capacitive grease, someone would have smacked me. Only PC overclockers seem entranced with the stuff. So I don't what it looks like. If you're not sure yourself then maybe someone else who uses the stuff can weigh in on whether it looks metallic. If you're not using silver stuff then I'd just leave it alone because chips are very sensitive and you could cause problems removing it. If it is the metallic stuff then I'd try *very carefully* to remove what you can. That means staying grounded and being very careful not to mechanically damage anything. In either case, I'd test the components to make sure everything is still okay. It's not cool to sell stuff with goop on it unless it's been tested with the goop in place.


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