benchmarks are one thing real world is another. unless you run applications that are going to benefit from quad channel ram and an expensive processor I would do what the last guy said...( 2600K and Z68) .. as far as components go, every MSI product except for 1 that I have owned died. Mostly mother boards. I try and use Gigabyte exclusively.
Gtx 580 is a capable card, but isn't the most balanced in terms of cost vs benefit ratio. If your on a resolution that is at or less the 1920x1080 I would opt for a gtx 560 ti, gtx 570, or a hd 6950, but that is just me.