I highly recommend the ASUS Maximus Gen z68 board. It is an mATX. but it works great and priced right. If you don't have any old PCI gear your good. becuase there are no legacy pci slots. That is the board I recommend. I love mine.
ASUS Maximus IV GENE-Z/GEN3 Z68 LGA1155 mATX 2PCI-E16 1PCI-E4 SLI CrossFireX HDMI SATA3 Motherboard - DirectCanada