For a system
using a single EVGA GeForce GTX 460 2Win
graphics card EVGA specifies a minimum of a 700 Watt or greater power supply that has a combined +12 Volt continuous current rating of 46 Amps or greater
and that has at least two 8-pin PCI Express supplementary power connectors
Total Power Supply Wattage is NOT the crucial specification in power supply selection!!! Total Combined Continuous Power/Current Available on the +12V Rail(s) rated @ 45°C-50°C ambient temperature, is the most critical specification.
You may find power supplies on the market that supply more than enough Wattage to run the system. However, many of them lack the Amperage capacity on the critical +12 Volt rail, which is necessary to properly power the critical components in the system (i.e. CPU and GPUs). This is the reason why graphics card manufacturers overstate the power supply wattage, usually by at least 50 Watts, to take into account those power supplies that have the weaker +12 Volt rail(s).
The PC Power & Cooling Silencer Mk II 650W (MK II-650)
, with its combined +12 Volt continuous current rating of 54 Amps
and with one 6-pin and one (6+2)-pin PCI Express supplementary power connectors
, is electrically sufficient
to power your overclocked system configuration with a single EVGA GeForce GTX 460 2Win
. The only problem is that it is deficient by one (6+2)-pin PCI Express supplementary power connector
You could get one of these adapter cables: http://www.newegg.com/Product/Product.aspx?Item=N82E16812706013