As mentioned, it could be a respun, rebranded, and repositioned RV670.
The G94 is similar to a G92 with less shader resources, and it's also possible that the RV730 takes a similar path relative to the RV770.
Speculation: Cutting the RV770's ALUs to half the number (-> 240) and using lower clocks (and possibly a lower power process) would cut costs and drop power draw significantly, allowing access to more systems.
Performance should be roughly RV670 class, depending on what improvements AMD has made in the RV670 -> RV770 transition.