New PSU/Mobo/Case

That NZXT psu should be fine. Not a bad deal.

Look for reviews of that NZXT PSU. On the old list at http://www.tomswiki.com/page/Tiere [...] ngs?t=anon, NZXT is on tier-5, "Do not buy." This one may be newer than the list, but in the absence of properly-done reviews, I would NOT trust it. Good sources for PSU reviews include jonnyguru.com and hardocp.com; I think pcpers.com may also test PSUs properly. Some sites just stick a multimeter on them, which provides useless information as to quality. The ones I linked do load tests (cheap ones croak, sometimes at 50% of their rated load), and check electrical noise with an oscilloscope. They also take them apart, offering relevant observations as to the capacity and quality of the parts used in them.

Bump

Before i start personally i dont like NZXT or MSI so your getting advice thats a little bias.

NZXT make some ugly cases, the only one ive seen that looks ok is the Tempest (seems like a copy of the Antec900) in any case you should be looking at a Tier 1 or 2 PSU for your system as jtt283 linked. Something like PCP&P, Corsair, Antec.

I assume you already have the 8800GT and the AMD cpu, so the mobo should be ok, but ive had MSI's die on me in the past so i look to Gigabyte and ASUS these days.