Quote from Flutterwry
6450 gets 3Dmark11 score of 480. A 450GTS gets 2100. I mean really, that is the lowest end card you can really go. IMO, Intel HD 3000 could probably do somewhat better.
You shouldn't compare gpu gaming power by artificial benchmarks.
But anyway the game will run, maybe not in 1080p, maybe not on high, maybe not with high FPS but it will run.What graphical settings and what fps it is considered playable differs from one person to another.
Just for the reference I completed the entire game on 1024x768 with everything turned down to low on 20-40 FPS.I could play it just fine but my friend couldn't stand a minute of it and said it's unplayable.