@Vishal, the onboard one will work if you are not having graphics card. look for a decent 500W PSUs from Gigabyte or Cooler Master if you have 2.5k budget.
Ok... one more query i have a pc with VIP gold smps...AMD 7750 , Gigabtye MA78GM-S2HP sometimes hangs, restarts arround 1hr......is this due to smps ? bijli one will work with this config ? or Gigabyte 460 W ?