Advice about instalation

Hey guys,I finally made the move and bought an E8400. Anyone has any experience with this processor and FSX?I have a couple of questions about this system I am building.1) I installed a fan on the case. What is better, to make it blow cool air from the outside to the inside? or to blow hot air from the inside to the outside? It is just a question of where should the blades point to.2) I noticed the heatsink that cames with the processor has some sort of thermal grease already on the contact area. Should I add any thermal stuff such as Artic Silver, or should I just leave that and accept that the stuff already there will do the job.ThanksLeo