That PSU is on the limit of providing enough power for the GTX465 It does not show total amps on the +12volt rail but usually 2 rails of 18 amps means about 30amps total. This might be the reason for your issues.
Here is EVGA's recommended PSU size; "Minimum of a 550 Watt power supply.
(Minimum recommended power supply with +12 Volt current rating of 38 Amps.) "