If you're interested in how your computer might fare with the still-in-development Battlefield 2142, AMD Zone has a preview of the game's performance with the latest beta build of the game. When looking at the scores, keep in mind "beta build".
"For our testing we ran Fraps for the same length of gameplay, recreating the same gameplay. There was no way to make a demo unless you have a server, and you can not currently make one with 2142. This means there could be some error in these results, but looking at them we feel they should be accurrate. Settings we pushed to maximum for everything, and AA was set to 4XAA or off for these results."