CM PSUs are near-junk, especially at the low end. Don't count on it for more than 430W; monitor the temperature of the air coming out of it during a long gaming session. It may also be missing claimed protection circuits (some of their low-end are). Short answer, I'd suggest replacing it with a quality unit. Five hundred watts is enough, but choose a quality brand like Seasonic, XFX, Antec, FSP, or Enermax/LEPA.
While I wouldn't buy a FX-4100 myself, if your games are running to your satisfaction, then I'd leave it alone.
il change my psu then,what about this processor should i replace it with i5 3rd gen? store keeper compromised me with all those specs like 3.6 ghz speed and 4 cores and 12mb cache ...but got to know later that this actually is merely dual core with 2 sub cores and also that amd scAle of calculating the speed/frequency is a way smaller when compared with intel. !!