600-750 W is good depending on whether you are looking forward at overclocking or not , and make sure you choose a good brand. your setup looks pretty good depending on how much you budget is those are very good specs.
Thank you for replying. My budget was little bit over 600€ and I had Corsair 600W on my list, but wanted to make sure how much I needed. Can I ask your opinion on that GPU ? I found it pretty good for my budget due I dont want to buy AMD stuff. (dunno why just own decision )
if you are going to buy an I5 K series with a separate heat sink that would mean you are planing on overclocking than i would suggest 700W to be safe and a good brand so in worst case scenario your psu wont fail easily. for the gpu that is NVIDIA graphics not AMD and it is the best you can get for that price.
P.S: i Saw you mentioned "600 EUROS" i guess you live in europe so i don't really know what kind of electronic stores you guys have over there. check them all for the best prices you are looking for a GeForce GTX 660 Ti . make sure it has the TI at the end of it. There is the GeForce GTX 660 and there is a big difference in performance between the two.