Thanx a lot for the replies MrFeathers and Nutnut. I am aware that AMD cards are better for Mining Crypto-Currencies. Did read Mr. Bushnell’s recent interview in the Guardian - http://www.guardian.co.uk/technology/2013/jun/25/bitcoin-successors-litecoin-freicoin
ATI 7870 and ATI 7950 would be too high an investment for me right now. Indian Rupees 16,000 and 25,000 right now. ATI 6450 and 6670 seem safer bets. INR 3587 and 5381 right now. US $ 1 = 60.70 INR right now. I hope these cards are compatible with the Mother Board and the Microprocessor.
Off to a short break and will return to the forum in a couple of weeks to start my Mining adevnture. Thanx again.