Linus was only pulling a little over 500W from the wall using a much higher configuration than yourself
3960x
Quadro 4000
GTX780
That being said you may even get away with a 450W PSU but i would not push it because components will age over time and you may or may not upgrade your system.
Getting a quality 500W will be your best solution however if you plan on getting, say a second gpu to SLI you could want to gett a better PSU right now, if that's the case a 650 or 700W will be adequate.
Of course! Would you say a 650 is enough for the setup above, but instead of a 770 a 780 Ti? Plus a few case fans and a blu-ray drive? My gut feeling is yes but again I don't have that much experience. Thanks.
650W is way enough realy for every single gpu setup. even 550W will be enough. But again for the same price grab the 650W. 780Ti or R9-290 (x) you will all be fine with 550 / 650W.
above 750W is only in question if you talk about dual gpu setups.
Thanks for your help & time. I went with the Corsair RM Series 650W. It was more than I wanted to spend but I know having a quality PSU is key, plus it should last quite a while. Nice features too. Newegg had a sale so I purchased it at the same price as the 550. It came to about $140 CAD shipped with taxes in. I might post some photos of the PC later in the month. Thanks again.