[Yardstick]

I think your best bet if you want to stick with AGP is the ATI 3850 AGP. My X1950 Pro died a couple of months ago and I had a similar dilema. Given the limited availabliity of AGP cards nowadays I was left with the options of: replacing the X1950 with a 2nd hand card off ebay, buying a 3850 for a decent premium over the PCI equivalent or going the whole hog and upgrading the entire system to PCI. I went with the latter.

I looked at the current Nvidia AGP offerings and they appear to be out of the game. You might have better luck 2nd hand but nothing they had available new was even comparable to the X1950 Pro.