I think it's a computer that uses out of date hardware and a POS power supply. Please edit your post to include all the information in the "How to ask for new build advice" sticky so we can help you build a system around current hardware. No new system should be using LGA 775 or DDR2.
It's also not a good idea to use a slow "Green" HD for your system drive or an IDE DVD burner.
Also, the other builds have a 5850 and X4 955 in them, while that one has a 5770. The 5850 would be much, much better.
batuchka's build is pretty similar to mine. I don't particularly card for MSI boards, so if you can find an Asus or Gigabyte that fits the budget, I'd go with that. You could also check out the Coolermaster Elite for the case. It should be cheaper than that NZXT.
@baldwondor: Just so you know, you should typically stay with the major brands for the PSU. Corsair, Antec, Silverstone, SeaSonic and PC Power & Cooling are the top brands. If those aren't available, you need to make sure the unit has Active PFC and a good efficiency rating (at least 80 Plus Certified).