Chugalug_ :
That is not how video cards work.
They are compatible based on the motherboard in your system, the software has nothing to do with it.
I beg to differ. The OP would still need Windows XP drivers for the video card, which a few of the latest cards do not provide. However, @Caleb1108, if the software you need won't run on newer versions of Windows, have you considering running an older version of Windows on a virtual machine (such as VMWare)? That would not require getting an older video card.
Edit: after posting this, I looked up drivers on nVidia's website, and cards up to the GTX 900 series (e.g. GTX 960, GTX 980 Ti, GTX Titan) have Windows XP drivers available, though the GTX 1080/1070/1060 cards do not. On the AMD side...