Nvidia never released such a card.
While enthusiasts are making their own RTX 3070 with 16 GB of memory and even with a switch between 8 and 16 GB of memory , the Taiwanese company Gxore decided to release a full-fledged RTX 3070 with 16 GB of memory.
The company showed such an adapter at Computex 2023. More precisely, the company showed some kind of video card, and the description indicated RTX 3070 8/16GB GDDR6. That is, the company is preparing both a regular version and an unusual one.
World’s first production GeForce RTX 3070 with 16 GB of memory introduced
It should be noted that the RTX 3070 16GB does not officially exist, and no one has mass-produced such versions. At the same time, Gxore is not on the list of official Nvidia partners, which, apparently, allowed her to be self-willed in such an unusual way.
There are no details yet. Given that the company specializes primarily in professional GPUs for wall displays, it is unclear in what form the unusual RTX 3070 will hit the market. In particular, the description indicates the presence of eight Mini DisplayPort connectors, which hints at a non-gaming audience.