Re: Good graphics card?
Really anything from nvidia with 2 outputs on it should be great. Just install the nvidia restricted drivers, then after a reboot install nvidia-settings package to configure your second display.
The other question is, are you planning to play games on it? If not, you could get by just great on a $50 nvidia card.
If you're looking at gaming, you can get 9600 series cards that fit your budget. If you're willing to go up to $200, you can find 9800GTXs, which would definitely be worth the cost difference.
"I was dead long before you were born, and I'll be dead long after you're dead."