I have Arctic Silver 5 and a Thermalright XP120 heat sink. Today I will be getting a CPU(OEM) and a motherboard. I was just reviewing the instructions for Arctic Silver at their web site. It says that I need to clean the CPU and heat sink using Arcticlean2. As far as I know, the heat sink and the CPU have never been touched with human hands. I could be mistaken. I don't know how these items are handled during the processing and shipping, but the heat sink is new, and I'm expecting that the CPU will be new as well. Do I need to clean these two items? or are they clean already?