what psu should get?

[Spaurtacus]

Build:
Intel Core i5-4460
MSI B85M-E45, Socket-1150
Crucial DDR3 BallistiX Sport 1600MHz 8GB
ASUS GeForce GTX 780 3GB PhysX CUDA
Toshiba Desktop 1TB SATA 3.0

should i get a 500, 550, 600, 650 or 700 W psu?

 

[Dark Lord of Tech]

One of the best 650w on the market , plenty for your specs.

PCPartPicker part list / Price breakdown by merchant / Benchmarks

Power Supply: XFX XTR 650W 80+ Gold Certified Fully-Modular ATX Power Supply ($94.99 @ NCIX US)
Total: $94.99
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2014-06-03 17:10 EDT-0400)

 

[Pondering]

Non modular XFX 750 Watts $70 but shipping is $11 unless if the order is $100+

http://www.ncixus.com/products/?sku=95616&vpn=P1750GTS3X&manufacture=XFX&promoid=1016

 

[sora]

Non modular XFX 750 Watts $70 but shipping is $11 unless if the order is $100+

http://www.ncixus.com/products/?sku=95616&vpn=P1750GTS3X&manufacture=XFX&promoid=1016

+1, NCIX generally has cheap prices and the shipping isn't even all that bad; the 750W will also give you a bit of upgrading space.