For a gaming PC, for the following parts are required and approximate prices are:
1. Motherboard- Rs.4000-6000
2. Processor- Rs.7000-15000
3. Graphic card- Rs. 5000-10000
4. RAM-Rs.2000-4000
5. HDD-Rs.4000
6.Power supply-Rs.2500
For a moderate pc you will need to pay around 25000 rupees. Your motherboard ( Is it this?: "http://www.gigabyte.in/Motherboard/GA-P61-USB3-B3-rev-10#ov") supports intel 2nd generation processors. It is a better option to upgrade to a new motherboard and processor. Please give me an approximate budget only then can I suggest a processor and motherboard.
If, in 15000 you need all components like graphic card ram and processor, I suggest you use your current motherboard and buy a second generation i5 processor. Your motherboard does not support integrated graphics so you will need a good graphic card also. Before going any further, please tell me all the parts you currently have and amount of money . Average gaming pc can cost upto INR 50000.