Forgive my ignorance here. I'm looking to build a budget gaming computer and have questions concerning what it is exactly I am looking for in a mobo. I have read about chipsets, overclocking, crossfire but can't exactly nail down what it is that I'm looking for. I see boards with USB 3.0 some have figures for overclocking the memory and I'm looking at PCI X 1,2,4,16 and not sure what is the most important aspect of picking a board. So I start with the chipset, then look for overclocking ability, then the speed of the PCI port? I'm looking for a general rule of thumb here, not a lengthy drawn out explanation, and maybe some reccomendations around the $100 range.