Always look for card that has GDDR3 RAM.
256MB GDDR3 is faster (even double) than 512MB DDR2.
GDDR3, Graphics Double Data Rate 3, is a graphics card-specific memory technology, designed by ATI Technologies.
It has much the same technological base as DDR2, but the power and heat dispersal requirements have been reduced somewhat, allowing for higher-speed memory modules, and simplified cooling systems. Unlike the DDR2 used on graphics cards, GDDR3 is unrelated to the upcoming JEDEC DDR3 specification. This memory uses internal terminators, enabling it to better handle certain graphics demands. To improve bandwidth, GDDR3 memory transfers 4 bits of data per pin in 2 clock cycles
There was GPU roundup in October 2007 digit issue.
Found this awesome card ASUS EN8600GT. This was damn fast and churned more frames than 8600GTS, which were 10k+. The price listed in the magazine for EN8600GT was Rs. 8,800. You should be able to get this card for 6.5-7k easily.
There is one more model ASUS EN8600GT Silent (without fan, has silent heatpipe). This one is nowhere near to the one mentioned above.
If you can get ASUS EN8600GT with 512MB of GDDR3 RAM for less than 7k, go for it. You will definitely get stellar performace/price ratio
