Anyone know which memory slots to use in order to get dual benefit? The are all blue...

I assume one and two....
Also, anyone know if an 80x80 hsf will fit with the cpu socket so close to the edge of the board, and hence to the ps? If not, up to what size? I don't want to use stock cause it spins too fast, and is quite noisy compared to an 80 mm.....Thanks.