Nvidia cards of 2013 or ATI

[Kiefer]

What is the bare minimum (economical, gets the job done) video card this year? Is there one that will do the job for years to come that might be worth paying a little extra today?

I currently play PotBs... but at some point the 21st century (normal high speed internet) will reach Vermont and I will probably venture on to other games.

I don't need flashy or crazy graphics, I want reliable graphics.

thanks for any tips/advice.