Elite Bastards posted a review on the Sapphire Radeon HD 4670 512MB video card

Compared to the RV770 core and its 956 million transistors on a 55 nanometre manufacturing node, RV730 is made up of 514 million transistors (also manufactured on a 55 nanometre process) and squeezed into a 146mm squared die. RV730 carries all of the same basic functionality as its big brother, from Shader Model 4.1 and DirectX 10.1 support through to the second generation UVD engine and hardware tessellation unit.

Into that transistor count, AMD have managed to pack the same basic amount of processing power as their previous generation high-end core (RV670), giving the Radeon HD 4670 a total of 320 Stream Processors to play with, which are arranged as eight SIMD cores, each of which sports forty Stream Processors (against ten cores with eighty Stream Processors in RV770).

Sapphire Radeon HD 4670 512MB video card review