For your budget, I'd recommend the Gigabyte P35-DS3L.
Newegg.com - GIGABYTE GA-P35-DS3L LGA 775 Intel P35 ATX Intel Motherboard - Retail
....or the DS3R, if you can afford:
Newegg.com - GIGABYTE GA-P35-DS3R LGA 775 Intel P35 ATX Intel Motherboard - Retail