Interesting, I can't find a card with the "9600" moniker on their comparison chart that shows 256mb of video ram. The ones on that chart all show 128. Hope the ebay auction isn't falsifying the amount of video memory. I'm sure Bruno could answer that definitively.
Anyway, that card has less than half of the performance ot ATI's latest top-of-the-line card (the X800). But I'm sure it costs a whole lot less, too (I don't know the pounds-to-dollars comparison to be sure).
If that card really does have 256mb of video ram, it should be darn good. The latest games are really going to push the limits of texture memory. Having more video ram is what lets you crank the texture sliders in the game up to "high" and not experience slowdowns.