I'm in the process of building a new system using an ASUS A7V motherboard with an AMD 900 MHz cpu. I purchased a Cooler Master heatsink and fan (DP5-6H11) and I'm not sure whether -or-not I need to put some heat sink compund on the cpu and heatsink. There's a patch of phase change interface material on the bottom of the heatsink that's supposed to melt when it gets hot enough and fill the area between the CPU and heatsink. Is this good enough or should I add heat sink compound?