Need help on a picking a PSU for a new build

[JSwaffs]

Gonna be making a new build but I'm unsure what power supply I should get. Thinking of getting an 850W PSU but unsure if thats overkill. Plan on playing an streaming high quality games. What wattage would suffice, any insight helps!

Specs I'm thinking are:
GPU: EVGA GeForce GTX 1080 SC ACX3.0
CPU: Intel Core i7-6800k
MOBO: Asus X99-A
RAM: Corsair Vengeance DDR4 3200 32gb (2x16gb)
Water Cooling: Corsair Hydro Series H100i V2
Case: Rosewill Nighthawk
Storage: 250g ssd and 2tb hdd
PS: if you think any of this is like overkill or not the best value for performance i'd love that input on any component.

 

[Isokolon]

850W is overkill.
a 550/650W would do quite easily.

also I'm not sure 32GB RAM are necessary.

 

[JSwaffs]

Isokolon got a pretty good bundle on the 32gb ram i was only gonna go 16 but the 32gb ram was cheaper with the bundle. And really only 650W is the 1080 that power efficient?

 

[JSwaffs]

Isokolon is rosewill a good brand of PSU I normally get Corsair PSUs

 

[Astrix-]

Yea about 650-750 watts is all you would need

 

[Astrix-]

Isokolon is rosewill a good brand of PSU I normally get Corsair PSUs

I like evga pretty much just because it sounds cool thats what i have in mine is a 400 watt evga

 

[Isokolon]

the 1080 uses up to 220W
the 6800 up to 125W
(both non oc)

with Rosewill it's the same as with Corsair - some are good, some a bad.
Capstone & Lightening series are pretty good
Strider is rather poor.

depending on your budget I'd go with an EVGA G3 or Super Flower Leadex II
a Corsair RMx, EVGA G2 / GS are quite good as well
so are Seasonic G, X, Prime; XFX XTR, TS (gold) and Super Flower Platinum & Golden King / Leadex (basically anything that has Golden or Platinum in it's name by Super Flower)
Cooler Master V or VS are good as well for that built.