heh invidia = envy.. becuase people envy anyone with an nvidia
nah, for real though.. the x850xtpe is the best card around, but with your budget you should go all out and get SLi 6800GT's which cost about the same as the x850 and would outperform to my understanding.
Processor: AMD FX-55 - Perfect, best cpu around.
VPU: ATI Radeon X850 XT - I would suggest 2x 6800GTS
HD: 2x Western Digital Raptor 73GB in Raid 0 - Change to 2x 36GB's in Raid for Windows. and add a 200gig 7200rpm or something.
Sound Card: Audigy 2Z Gamer - Great
Optical Drive: Lite On 16x Dual Layer DVD +/-RW - Fine
MoBo: ABit "AX8" or "AV8"... I don't know.. - For the 6800GTS, get an ABiT a8n sli deluxe
RAM: 2x Corsair XMS 512MB DDR PC-4400 - yeah.. great
CASE: Lian-Li - the best cases imo.. fits your request perfectly.
Speakers - if u can afford them - Logitech z-5500 $250
just thought id add in my own opinions