PSU is often neglected in building rigs. A good PSU acts as 'insurance' against your components. Most time it's advised on forum that one must not skimp on PSU. Yes, one might be on a tight budget. But I think 65-70k is good budget for a gaming rig with good PSU. My suggestions for PSU would be either Seasonic S12 II 520 or Antec one suggested by Sunil. Once again I would like to say that oveclocking would not help much in gaming. Hence instead save money in that department and get better PSU. IF you still have some money left, get better GFX card. Hope this eases out some confusion. Chers !