That power supply will power your system just fine.
I don't imagine your quad will bottleneck your system. Also, I'm unfamiliar with your motherboard. On newegg like you said, it says pci express 2.0 x16, are you sure this isn't the case? Regardless it will be backwards compatible with pci express x16, however, I'm not certain as to whether or not that will cause a bottleneck.