Take it with a grain of salt but VideoCardz came across rumored specifications of both the GA103 and GA104. The GA103 is said to be a higher-end model like the GeForce RTX 3080, while the GA104 is expected to be used for the GeForce RTX 3070 series. The rumor originated on Twitter, from a user called KittyCorgi, and on the Asian MyDrivers website:
According to the rumor, GA103 GPU would supposedly feature 60 SMs (Streaming Multiprocessors “Ampere”) while GA104 would end up with 48. The weird naming convention (103) is something we do no fully understand, NVIDIA does not use uneven numbers for high-end GPUs.The rumor points to 3840 CUDA cores for the RTX 3080, and 3072 for the RTX 3070. Guess we'll find out more in the coming weeks and months. The next lineup from NVIDIA is expected to offer big gains in term of energy efficiency, as well as much higher ray tracing performance.
If this data is to be believed then RTX 3080 would get GA103 GPU and GA104 would be used for 3070. This is the same approach as we had for the original Turing series where RTX 2080 received the TU104 processor and 2070 was based on smaller TU106 silicon. This has changed for the SUPER series. The rumor also mentions a 320-bit bus for RTX 3080, which would allow 10/20GB memory configuration.