If this news from Fudzilla is true, then some partners of NVIDIA are going to offer 1GB versions of the 9600 GT.  Let me say that again – 1GB of frame buffer on a card with mid-range performance.  If this is true, and performance differences between the 512MB and 1GB versions are what I am guessing they will be (~0-1%), this could be the worst idea I’ve heard in a long time.
Nvidia plans to launch two version of the Geforce 9600GT. The reference design has 512MB memory but some partners will launch a bit more expensive 1GB version.

Memory still plays an important role in a mind of consumer and ATI and Nvidia are already selling Radeon 3850 1GB as well as 8800GT with 1GB. Geforce 9600GT with 1GB doesn’t come as a big surprise as the memory got cheaper but unfortunately you cannot count on a huge performance increase with 1GB card over the 512MB.

Nvidia uses DDR3 memory with 256 bit memory interface and it was a time to move from rather limiting 128 bit interface that was used for years.