It might help you decide what's best. I wouldn't take the number it gives you at its face value. If it tell ya you need a 430W PS then maybe getting a 500W one is a good solution.
Also, if I ever upgrade to a newer video card, say, HD 4870. Or 4870x2
Would 450vx handle it?
Maximum Power 450W
Fans 1 x 120mm Double ball-bearing fan
PFC Active
Main Connector 20+4Pin
+12V Rails Single
PCI-E Connectors 1 x 6Pin
SLI No
Modular No
Efficiency Up to 85%
Energy-Efficient 80 PLUS Certified
Over Voltage Protection Yes
Input Voltage 90 - 264 V
Input Frequency Range 50/60 Hz
Input Current 9/ 4.5A
Output +3.3V@20A,+5V@20A,+12V@33A,-12V@0.8A,+5VSB@2.5A
The 450vx and the PC Power and Cooling 500w would be fine for the initial system, in fact excellent. They would also handle the single 4870. The 4870x2 would be too much for them. The minimum i'd go with your system and the 4870x2 is the PC Power and Cooling 610w, Corsair 650w and i'd be more comfortable with the 750 Corsair or PC Power and Cooling Silencer 750w.
The 650 would be overkill for the current system, but not for a 4870x2. It's less efficient only when going with really powerful (>1000watt) power supplies. A 650 won't be any less efficient than a 450, though.
You can decide, but for $11 more, I'd get the tx 750w PSU. It has 4 x 6+2pin (8 pin) PCI-e power connectors, so if you add another GPU later, you won't have to get any extra converter cables!!!
You are about to answer a thread that has been inactive for more than 6 months. If you still wish to proceed, please ensure that your posting is original and does not duplicate or overlap any prior responses to this thread.