i have an assembled pc of the following configuration CPU 3.0 Mghz intel Ram 512mb 915glvg intel mobo dvd writer Kindly advise on the extra graphics card that can be added to play games on this pc please do not suggest very expensive ones thanks in advance

nvidia geforce 7 such as 7600gs. Overall performance is amazing for the price if you don't play games over a web network(like World of Warcraft).I use 1024x768 resolution with maximum overall settings and play recent games like Loki or not so recent like Oblivion without problems.You will see the pouring rain,the leaves in the trees that keep moving like wind is present etc.and all the fine details that make these games so interseting to watch and play. You can choose 256 Mb Ram over 512 Ram and save some more money.The card video processor is more important than the RAM. For a Radeon card choose the X1650 but nvidia is preferred in this price range. The nvidia geforce 6 (like the 6200)is a cheaper card with a lot less to offer in the long term for games. If you intend to play over a web network save your money for a geforce 8800.