At least some claim
Some of Nvidia partners have said that they will be ready to showcase Nvidia's Geforce 9800 cards at Cebit. So, the launch will be either at Cebit or shortly before Cebit.
We will tell you a more accurate date when we get it, but it looks like Nvidia is doing the final tweaks to it; and at this time the company should be starting production to reach availability at Cebit.
For all of you that might not know Cebit starts on March 4th and this might give you a better time frame. At this point it looks that Geforce 9600 launches on the February 21st, while 9800 should be launched between then and March 4th.
