Theraxel :
PizzaTheHutt :
Yes. Thermal paste is needed as your heatsink will be removed and a new CPU will be put under it - clean off the old thermal paste and apply some new paste - about the size of a grain of rice in the center is all you need, then put the heatsink on and you are done.
Thanks for the answer and detail.
Both the CPU and MoBo will be bought new retail so does this still apply?
The CPU you are buying comes with a stock cooler that will have thermal paste pre-applied so you don't need to if you are using that cooler. Otherwise, you will, i.e. if you are using an aftermarket cooler than you will most likely need to apply thermal paste.