Quote Originally Posted by Eastcoasthandle View Post
The smoother the IHS the less "tiny air gaps" you have. That's why it's a no, no to leave a IHS at 600 grit lapped (for example). It's better to have a smooth surface, sometimes that's interepted as a reflective finish. In other words, the less ridges and uneven spots you have the more reflection you obtain. But lets be honest, mirror finishes are only obtained through the use of Brasso, etc. Lets be clear though the purpose of lapping is:
-remove the tin as it's not good for thermal heat transfer
-reduce the IHS thickness. The thinner the IHS the more likely you decrease the delta between the Core and IHS temps
-make the IHS as smooth as possible. This will reduce the amount of microscope air pockets. The less thermal compound you need the more contact you have between the HS/WB and IHS which results in better heat transfer.
-make the IHS as flat as possible. Making the IHS as true as possible ensures good contact with your HS or WB. Thus allowing the HS or WB to do it's job by removing the heat from the IHS.
I would have to disagree, the thermal compound if properly applied will not leave any air gaps, if you polish it, it's the IHS, then the polished metal, then thermal compound, then HSF, ow it's IHS, arctic silver, HSF, fewer layers mean better conductivity.