extremely slow performance..card to blame?

[mjf6866]

hello everyone, this is my first post here!

i've been itching to play this game since i first saw videos online, but i never had a machine that was capable of playing it at a framerate that was good enough.

well, i was just given a Dell Optiplex 780 with:

Intel Core 2 Quad 3.0ghz Q9650 CPU
Win7 64bit SP1
6GB DDR3
256MB Nvidia GeForce 7300SE/7200 GS GPU

i know that graphics card is junk, so i ordered a Radeon HD7750 1GB DDR5 card from amazon HOPING that will make this game run smoothly on this system because when i run the demo now, its GOD AWFUL choppy even on low settings.

so could the card i have in it now be the reason for the poor performance? i should see that new 7750 next week, but was hoping to get some feedback from people that have the game. i've been out of the PC gaming loop for a while and Amnesia and Arma2 (for the DayZ mod), and that runs like shit too, are the only reason right now i'm hoping i can get this system to run them smoothly!

thanks for any feedback!