What PSU would I need to buy with these components ?

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System Power Supply Requirements for a single MSI R9 280X TWIN FROZR GAMING OC EDITION
AMD specifies a minimum of a 600 Watt or greater system power supply. (Minimum system power requirement based on a PC configured with an Intel Core i7 3.2GHz 130 Watt TDP processor.)
the system power supply must also have a maximum combined +12 Volt continuous current rating of 42 Amps or greater
the system power supply should also have at least one 75-Watt 6-pin and one 150-Watt 8-pin PCI Express supplementary power connectors.

Total Power Supply Wattage is NOT the crucial factor in power supply...
System Power Supply Requirements for a single MSI R9 280X TWIN FROZR GAMING OC EDITION
AMD specifies a minimum of a 600 Watt or greater system power supply. (Minimum system power requirement based on a PC configured with an Intel Core i7 3.2GHz 130 Watt TDP processor.)
the system power supply must also have a maximum combined +12 Volt continuous current rating of 42 Amps or greater
the system power supply should also have at least one 75-Watt 6-pin and one 150-Watt 8-pin PCI Express supplementary power connectors.

Total Power Supply Wattage is NOT the crucial factor in power supply selection!!! Sufficient Total Combined Continuous Power/Current Available on the +12V Rail(s) is the most critical factor.

Overclocking of the CPU and/or GPU(s) may require an additional increase to the maximum combined +12 Volt continuous current ratings, recommended above, to meet the increase in power required for the overclock. The additional amount required will depend on the magnitude of the overclock being attempted.

EVGA SuperNOVA 650 G2 (220-G2-0650-Y1)
OEM: Super Flower
maximum combined +12 Volt continuous current rating: 54.1 Amps <===== More than Sufficient
two 75-Watt 6-pin and two 150-Watt (6+2)-pin PCI Express supplementary power connectors <===== More than Sufficient
Ambient Temperature Maximum (i.e. without derating): 50°C
Full Modular Output Cables: Yes
Meets Official Intel Haswell Compliance: Yes
• 80 PLUS GOLD Efficiency Certification
• 7 Year Limited Warranty with registration
Link: http://www.evga.com/Products/Product.aspx?pn=220-G2-0650-Y1
 
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