What is the equal to the HD 7870 XT 2GB

I want to know so i can bargin hunt for either the HD 7870 XT 2GB. Or its conterpart in nvidia.

660ti is the nvidia equivilent but I would say the hd 7950 with a decent cooler on it is the best as it has one of the highest overclocking potential of any current gen cards.  You can get past stock 7970 ghz edtion performace with a overclock at around $300 is crazy.