And the requirement for the GTX 680 are: Minimum of a 550 Watt power supply.
(Minimum recommended power supply with +12 Volt current rating of 38 Amps.)
Two available 6-pin PCI-E power dongles
is my PSU good for that and will it overheat the GPU easy?
it says that you need 550 watts, you have 650..... good
it says you need 38 amps on the +12 rails, that psu has 54..... good
it says that you need 2 6 pin PCI-E connectors, that psu has 2 6+2 connectors..... good
OCZ makes OK power supplies so i think that you will be fine with that psu for the card