I would recommend an Asus 750i chipset,extremely stable been a good for motherboard for me.
1.Price is $US160~
2.Good Overcloker,know people who gets 3.6ghz on Q6600 on this board
3. x2 Pci Express 2.0 Both Runing at 16x(For Future purposes)
4.Support 45nm CPU's if you plan on gettin on or in the future.
Link.
Asus P5N-D Motherboard - NVIDIA nForce 750i SLI, Socket 775, ATX, Audio, PCI Express 2.0, Gigabit LAN, SPDIF, USB 2.0, Firewire, Serial ATA, RAID at TigerDirect.com