[The Exiled]

nVidia RTX 4080 12GB and 16GB based on different chips, vastly different shader counts

When we first got news about nVidia's upcoming GeForce RTX 4080 "Ada" coming in 12GB and 16GB variants, we knew there was more setting the two apart than just memory size and memory bus-width. Turns out there's a lot more. According to detailed specifications leaked to the web, while the 16GB variant of the RTX 4080 is based on the same AD103, the second largest chip after the AD102; the 12GB RTX 4080 is based on the smaller AD104 chip which has a physically narrower memory bus. It looks like nVidia is debuting the RTX 40-series with at least three models — RTX 4090 24GB, RTX 4080 16GB, and RTX 4080 12GB. The RTX 4090 is the top-dog part, with the ASIC code "AD102-300-xx." It's endowed with 16,384 CUDA cores, a boost frequency of up to 2.52GHz, 24GB of 21 Gbps GDDR6X memory, and a typical graphics power (TGP) of 450W, which is "configurable" up to 600W.

The RTX 4080 16GB is based on the AD103-300-xx" comes with 9,728 CUDA cores, a boost frequency of 2.50 GHz, and 16GB of 23 Gbps GDDR6X memory across a narrower memory bus than the one the RTX 4090 comes with. This card reportedly has a 340W TGP configurable up to 516W. The GeForce RTX 4080 12GB is positioned a notch below its 16GB namesake, but is based on the smaller AD104 chip, with 7,680 CUDA cores running at speeds of up to 2.61GHz, 12GB of 21 Gbps GDDR6X memory, and a TGP of 285W that's configurable up to 366W. It's interesting how the leak includes not just TGP, but also maximum configurable TGP. The various board partners will utilize the latter as their power limits to achieve overclocked speeds. Even the nVidia Founders Edition board is technically "custom design," and so it could feature higher-than-stock TGP.

Izvor: TechPowerUp