tiny voices said:
You probably want a new PSU, that one is very low quality and 600w is a lie. Replace it ASAP.
You want to stick with Antec, XFX, Seasonic.
Changing to an i5 will not affect gaming at all. The saved money to take the GPU up to a gtx770 will make a large difference in performance.
Ok so I will buy a new PSU and get a 8gb ram. What i5 processor would you recommend me?