Just buy the cheapest. BTW, Palit has released 9600GT Super 1GB GDDR3 Edition which costs 6K. Might want to consider it if you intend to show off your GPU memory, but remember that this means unless you run Linux, BSD, Solaris, Macintosh 10.5, or Win64, only 3GB desktop RAM can be used since win32 has a limit of 4GB RAM. 512MB version is 5.5K now, so I am surprised at how cheap GDDR3 has become, its even cheaper than standard PC-DDR3.
if u want just performance, go for XFX - real gud, though expensive.
but for a gpu with an excellent price-performance ratio, go for palit - they make graphics cards that really giv a bang for ur buck.
You can go for the Sparkle 9600GT 512MB GDDR3 for Rs. 5500.
It's a half-height card AFAIK, meaning half the size of the regular 9600GT(not PCB). It's heat dissipation is surprisingly lesser and it takes MUCH MUCH lesser space, ideal for a smaller/lower-mid sized cabby with only one fan or none.