The CPU cooler power take would be very small compared to such as the CPU or the GPU.
Intel® Core™ i5-4670K vs.
Intel® Xeon® Processor E3-1230 v3
If you are not really serious about the overclock (which I wouldn't take under 4.2Ghz or so) I would stick with the Xeon. The i5 is quad core CPU with four logical cores available to the system. The Xeon is quad core also but with eight logical cores available to the system plus with the turbo ratio overclock, all cores would be under load at 3.7Ghz (which could act as 8 cores at 3.7Ghz for certain applications). And with the passive cooler no noise would be ever an issue. The i5 has Intel HD4600 integrated GPU, the Xeon doesn't.
I would stick by my previous statement that even the 450W XFX would be more that enough for your needs.
I wait till more senior members comment on this section but long term the Xeon would be better I would say plus you wouldn't have to deal with the problematic overclocking (turbo ratio overclock is nothing like that).