Processor alone may fetch good bucks. That is a really good processor. By the way, you still can pull few more years with it.
Rs. 3k -> G41 based motherboard
Trade the RAM -> old RAM + Rs. 600/- -> 4GB DDR-III 1333 MHz (market price Rs. 1100/-)
Rs. 2k -> for a Corsair VS450
Rs. 8k -> HD7770 1GB GDDR5
Rs. 13/14k upgrade, which last for another couple of years