cheapest board with usb3.0 although no support for sli/crossfire and I don't think you can find a board in this price range that will.
Also you cant utilize pcie 3.0 with a i5-2400(sandy bridge). you would need a Ivy Bridge cpu for that.
AsRock is a good mobo but it has only 1 year warranty.
I need 3 years warranty mobo.