AMD's new GPU is called "Tahiti LE" even though it's a part of the Radeon HD 7800 series, because it is derived from the same 3.5 billion-transistor "Tahiti" silicon that goes into making all Radeon HD 7900 series products and not the "Pitcairn" silicon that goes into making the HD 7870 GHz Edition and HD 7850. The new SKU drops the "GHz Edition" moniker by featuring lower clock speeds than the HD 7870 GHz Edition, but it makes up for that with more pixel-crunching muscle.
Tech Power Up
http://www.techpowerup.com/reviews/Club_3D/HD_7870_jokerCard_Tahiti_LE/
