A GTX760 needs only a decent 500w psu.
On the rest of your build:
1. 4gb of ram is not needed, do not pay extra for it.
Read this: http://www.pugetsystems.com/labs/articles/Video-Card-Pe...
2. Z78 is a sandy bridge chipset. You want a Z87 based motherboard. I think your are ok, just got the name wrong.
3. I do not much like all in one liquid coolers when a good air cooler can do the job.
A liquid cooler will be expensive, noisy, less reliable, and will not cool any better
in a well ventilated case.
And... I have read too many tales of woe when a liquid cooler leaks.
google "H100 leak"
4. I will not build today without at least a 120gb ssd for the os and some games.