I an looking to build a pc that can run games on normal or higher at 60 fps. I can't go over $900 and I would like this pc to be upgradable and use the cm storm scout 2 case. What I mean by upgradable is that I would like it to be capable of sli or CF. I don't need a monitor, mouse, or keyboard, but do need an OS. If it is possible to fit in a SSD that would be awesome.