please suggest me which one to purchase among the following graphic cards?
http://www.flipkart.com/msi-nvidia-n660-gaming-2gd5-oc-geforce-gtx-660-gaming-2-gb-gddr5-graphics-card/p/itmdt7dhyx2agbr5?pid=GRCDT7DHYX2AGBR5&otracker=from-search&srno=t_3&query=gtx+660&ref=38cee733-f9e7-47dc-99a8-62e8187dabe0
http://www.flipkart.com/msi-amd-ati-r9-270x-gaming-2g-2-gb-gddr5-graphics-card/p/itmdpvgbm5mfapyv?pid=GRCDPVGBM5MFAPYV&otracker=from-search&srno=t_2&query=r9+270x&ref=5f9a0ac9-7842-4c7c-9373-4ee967c81a82
http://www.flipkart.com/sapphire-amd-ati-radeon-r9-270x-boost-oc-2-gb-ddr5-graphics-card/p/itmdtp5j69ssu9gj?pid=GRCDTP5J69SSU9GJ&otracker=from-search&srno=t_1&query=r9+270x&ref=5f9a0ac9-7842-4c7c-9373-4ee967c81a82
consider all the factors and suggest me the best one.Thank you.
http://www.flipkart.com/msi-nvidia-n660-gaming-2gd5-oc-geforce-gtx-660-gaming-2-gb-gddr5-graphics-card/p/itmdt7dhyx2agbr5?pid=GRCDT7DHYX2AGBR5&otracker=from-search&srno=t_3&query=gtx+660&ref=38cee733-f9e7-47dc-99a8-62e8187dabe0
http://www.flipkart.com/msi-amd-ati-r9-270x-gaming-2g-2-gb-gddr5-graphics-card/p/itmdpvgbm5mfapyv?pid=GRCDPVGBM5MFAPYV&otracker=from-search&srno=t_2&query=r9+270x&ref=5f9a0ac9-7842-4c7c-9373-4ee967c81a82
http://www.flipkart.com/sapphire-amd-ati-radeon-r9-270x-boost-oc-2-gb-ddr5-graphics-card/p/itmdtp5j69ssu9gj?pid=GRCDTP5J69SSU9GJ&otracker=from-search&srno=t_1&query=r9+270x&ref=5f9a0ac9-7842-4c7c-9373-4ee967c81a82
consider all the factors and suggest me the best one.Thank you.