[email protected] wrote: > On 3/12/09, Clark Martin wrote: > >> If the Heatsink / Processor combo is supposed to use grease then >> conductivity isn't an issue, you assume the CPU and heatsink will >> connect electrically. If you don't want them to connect electrically >> you use an insulating spacer like a mica insulator. > > You're NOT supposed to use grease. You're supposed to use thermally > conductive compounds or adhesives. Engineers deliberately distinguish > between grease (hydrocarbon/oil based lubricants) and thermal compounds > (homogeneous polymeric organosilicon substances) so that the ignorant > don't go to the local auto parts store, pick up a tube of grease, and > apply it to their computers. An unmentioned someone is being bull-headed > in this matter. :-) (Remember, ignorance isn't a sin. It merely means > one hasn't been exposed to the issue.) See: > <http://www.arcticsilver.com/as5.htm> > > As discharging the processor's heat is the goal, thermal conductivity is > critical. Thermal compounds and adhesives are intentionally designed to > conduct heat and to be electrically non-conductive. Mica would satisfy > the electrical requirement but grossly fail to sufficiently conduct heat.
Mica is commonly used as an electrical insulator and thermal conductor in in electronics. It seems to fit both requirements well enough. No, it's not a great thermal conductor but most things that are electrical insulators aren't. That is why it is kept very thin. do a web search on "thermal grease" <http://www.google.com/search?client=safari&rls=en-us&q=thermal+grease&ie=UTF-8&oe=UTF-8> Most or all refer to a substance for conducting heat in electronics. Whether or not "grease" is the proper term here, it IS one used extensively. -- Clark Martin Redwood City, CA, USA Macintosh / Internet Consulting "I'm a designated driver on the Information Super Highway" --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed Low End Mac's G3-5 List, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/g3-5-list?hl=en Low End Mac RSS feed at feed://lowendmac.com/feed.xml -~----------~----~----~----~------~----~------~--~---
