im replying again, bec its yours is first build. pls dont compromise in PSU. if you are on less budget then no other go you should choose according to it.
but PSU are essential components that saves your entire PC. so please dont do cost cutting in PSU. even you choose 600w too if you have budget. its a necessary thing for your PC, if you do a upgrade in GPU or CPU etc.. in future. so think according to it before you getting one.