i'd also dump the velociraptor, unless you really want to,
They are fast at loading games. And have a quick acces time. If you have the budget i'd say go ahead. But I would buy a 640GB Western digital as a 2nd hardrive. To store all your music, films etc...
4870X2 has enough juice, 800watt is more then enough, i'd switch to a 620 watt corsair hx, or OCZ gamexstream 700 watt, that will save you some
make sure you use vista x64 for that 6 gig