Ligish :
Kindly suggest a good graphics card for amd fx 4100 quad core processor
You didn't say what your budget was, so my guess is that you want something decent without liquidating your pockets in the process. With that said, I'd suggest the Sapphire Radeon 7790 OC GDDR5 Dual-X OC. Here's a link to the card with specs on Amazon.com:
http://amzn.to/1kXavim
It's a decent card that handles quite well for the price.