just a suggestion, ur system dun require half the output of a Corsair VX 450.
an VX 450 can handle a quad along with a 9800GTX+ or a 4850.
though not much PSus in here comes close to the efficiency of the VX, but there are many gud ones too, even if not as efficient.
Zebronics Platinum 500 for 1.8k is a gud one. My frend is using an oced X2 with a 9800GTX with a couple of HDD w/o ny problem for around 2.5yrs now[earlier he had a 7800GTX] .
Even im using an oced X2 n an 8800GT with a Zebronics Pro 550[3k]...works like a charm.
if u goin for 4670, then get a 2k PSU, orelse if its 9600GT, get a gud one...
the green one jst doesnt need a 6 pin connector, consumes power close to the real one...but thru the PCI-E slot itself. Those power if drawn from the 20+4 pin's 4 pin to the mobo's PCIE buses..... nyway ull need a powerful PSU.