Maximum PC

I'm currently looking to build an AMD computer for gaming/occasional video editing. I've done alot of research on the parts I'm getting (i pretty much purchased them already), but I'm not too sure what power supply i should get (wattage, brand, etc). I was considering a 500/550W PSU for this rig, but I've considered overclocking in the future. What power supply should i get without going overboard. considering the following parts?

CPU: AMD Phenom II x4 980BE (@3.7GHz)
Aftermarket Cooler: Cool Master Hyper
Motherboard: ASUS M5A88-M (Micro ATX ; AM3+ socket)
RAM: AMD Memory Performance Edition (4GB x 2; DDR3-1333MHz) [might upgrade that to 2000MHz in the future]
GPU: Sapphire Radeon HD 6790
ODD: Lite-ON DVD Drive
HDD: Western Digital 500GB (6GB/s SATA)
Case: NZXT Vulcan Micro ATX case

I'm also considering getting a fan controller, card reader, and i might include some case lighting later on (additional fans with LEDs, cathodes, etc). Any help would be greatly appreciated.

"pretty much" and have are too separate entities. Either you have or have not purchased these parts.

If you have not, what is your budget for a build? What is your budget for your power supply? Afford the best that you can, more is better and there is no such thing as going overboard (hehe). But honestly, You'd be set with any decent 500-600w PSU, you're not really sucking a lot of power considering the 6790 isn't a power hog.

As for AMD, if you got the budget, stick with Intel's i5/i7 over the x4. If you want to stay with AMD, pick the x6 over the x4 for video editing. Even the cheap i3's will hit a better price/performance ratio for video editing tasks than similarly priced x4's, although the i3's can't overclock like the x4 BE's can... Even then, if you got the cash for the 980 BE, invest a little bit more for the i5 2500k that can clock to 4.6-4.8Ghz with a cheap CM 212 or EVO cpu cooler. Or just wait for the new ivy bridge chips that will yield 5-15% increase for the same price in multi-threaded apps.