Geforce 9400 GS is 8500 GT with different name tag
 

It first launched as 65nm part and it was slowly replaced with 55nm chips. Now Nvidia has a better plan. It wants to rebrand the chip that we knew as Geforce 8500GT and simply sell it as Geforce 9400GS.

This is where the 128-bit memory interface comes from. There is only one problem for Nvidia, G96 the chip behind both 9400GS and 8500GT costs around $30 which makes it hard for Nvidia and its partners to make enough money of these cards.
http://www.fudzilla.com/index.php?op...88&Ite mid=34