What dual core processors are you talking about? What socket type is your current board? Were you wanting to add dual core to your current board? Your listed processor type can be got for the older 754 and newer AM2 sockets. You say you are getting micro atx case because your current board is micro atx. If it's a socket 754 board they are being phased out and dual cores don't fit it anyway so you'll need a new board for dual core.