Hey Javamonsoon,
If you look at the memory bandwith on the 9800 is 57.6, while the bandwith the 250 is 70.4 almost 20% better. Which translates into better frame rates in games. Now this is not going to be a 20% gain (in game), but it could be the difference in what settings you are using when playing and approximately 10% better benchmarks.
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