I don't think there is any information on the GTX5xx cards. We just got the GTX4xx cards and they are still working on bringing us the rest of the line up. They are working on the GTX5xx cards for sure, but at the moment most of us are wondering about the rest of the lineup. I don't think I'd be looking for info on the GTX5xx for at least 6mo. A year from now is more likely.