are you going to overclock?
If so, get the k version, else you are fine with a non k cpu.
GTX980 Ti will work fine with a 750w but if you plan to sli in future, than best is to get a 1000 w psu
my theory is more PSU power is always good. You dont want to get the "just enough" which makes upgrading parts in future difficult. A PSU can also last for 7 years (the better ones) so why not just get a better PSU now?
