Ok couple words of advise since I build my own systems for me and my son
First ... dont get any motherboard with on board video, it will end up giving some kind of conflict or problem eventually ... usually sooner than later
Second ... Think about buying a motherboard set up for the type of video card you prefer to run ... example being my motherboard is an N-Force series specifically for NVidia products, it doesnt play well with ATI stuff though. My kids is specific for ATI ... cause he doesnt listen to me and wanted a radeon
Third ... This one is a biggie ... by a BIG power supply. 580w probably wont cut it long term with todays high power high performance video cards. Consider at the very least a 650w unit but personally I wont go less than 700w.
Fourth ... put your money in your memory and vid card .. the rest can be found on the cheap. I run dual vid cards and 4 gig of crucial heat sink equipped memory. That will do more to giving you high performance than anything else.
And last ... build it your self and buy everything on newegg ... you'll be able to build a better rig and have fun doing it and learning as you go. plus newegg rocks LOL