So my computer has been running fine and I decided to get a AMD 7870 and a new power supply (750watt Rosewill). My motherboard is an atx micro and I have a i5 intel cpu processor. The problem I am having now is that when I plug the graphics card in and try to start up the computer to load the drivers, my screen get stuck on motherboard start up screen. The HDD light on the tower also stops blinking at that point as well. The computer runs fine when the graphics card isn't plugged in but get stuck when it is. HELP!