X99 Power Requirements

I'm upgrading from a Z68-based Ivy Bridge system to a X99-based Haswell-E system. This will be my first time going to a high-end platform. Will my 3-year-old Kingwin Lazer Platinum 550W be powerful enough for it? I suspect it will, but just wanted to pass it by y'all here first. Here are the rest of the specifications:



ASUS X99-A

i7-5820K, probably going to mildly overclock

GTX 760 (single, no SLI planned)

A lot of hard drives and SSDs!

Several 120mm fans



Also, to make this question more useful for future readers, how much more power does the X99 platform use compared to an otherwise identical P67/Z68/Z87/Z97 system (i.e.: same class of motherboard, same video card, etc...)?

X99 Power Requirements