Uh, just find a motherboard that supports PCIe and you theoretically should be good to go provided that it isn't terrible. PCIe 3 GPUs will fit in to PCIe 2 slots on motherboards but seeing as you're running with AMD you'll probably want a motherboard with Crossfire support in case you're ever considering upgrading (seeing as you're going cheap-ish on the GPU I thought I'd make this assumption).
Although, it's pretty hard to suggest a motherboard to you without a price range.