Its another crap card. GS, it should be a bit weaker then the 9500GT. (which has about the power of the 7300GT, so the 9500GS should still be in the junk category.) 9500GS x 4 (or maybe even 6) ~ 4850.
Don't touch parts that are "500" ones; anything below "600" means that it's generally a LOW-END part... And GeForce 9000 was the generation BEFORE the one that compares to HD 4000. Yes, it might've been priced close to the 4850, but that's because Staples charges an outrageous fortune for video cards.
The factor between the 9500GS and 4850 is far more than what 4745454b suggested; I'd peg it more like the 4850 being 10-12 times as powerful.