John Davies :
i have a 650 wot psu would gwting 4 gb verison be beter then the 2 gb would over clocking my cpu make mutch difrents
Depends on the quality (Brand) of your psu
But yes you should definitely oc that cpu! It was built for it!
4gb version gtx 960? it is not worth it, unless you are wanting to sli
I personally would get a r9 280/280x/290 over the gtx 960,
only time ill start considering Nvidia is gtx 970/980 range (even then id probably pick 290x just for the price), or if I have crap psu, and dont want my system failing in a year from too much power draw