I'll be more blunt.
The parts list LOOKS impressive but then you spot an item like the 512MB on the video card. Even a paltry 20 dollar ATI 5450 comes with 1GB. Something fishy there. If you want a top flight performer you know the basics to hit.
That's just one item. There could be more. My questions were to you since you are there and might know why they or you picked an odd item.