The list is at

http://www.tomshardware.com/reviews/gaming-graphics-card-review,3107.html

I pick up cards at newegg, amazon and fry's at times.

Even the 99 buck cards can run at medium so at least we've got to that point today. However your gamers tend to be either budget or want that card at the upper extreme since they know it will give them the edge in online play (debateable?)

Nice choice of CPU so you shouldn't worry about that for now.
Bob