That motherboard doesn't support sli but it does support crossfire so I would consider getting r9 380 instead. I would also consider getting at least a 500W power supply.

Considering this is a budget build with no future proofing at all, the graphics card would be the least of my problems. With crossfire, I would then need to get a better CPU to avoid bottle necking. Then I would need a new PSU, motherboard, case (the case is too small to support an additional graphics card). And by then I've spent another $500.