As per Chiphell sources, NVIDIA’s higher-end Ampere graphics cards may feature 10GB to 24GB of VRAM. As you can guess, the RTX 3080 is likely the 10GB card and the RTX 3080 Ti packing a massive 20GB memory buffer. Lastly, the RTX Titan or the RTX 3090 will come with 24GB of memory. This probably means that the so-called 40GB+ variant is a Quadro or maybe even another Titan.
It seems that there’s no trace of a 16GB variant that is expected to the default memory config for AMD’s Big Navi. Regardless, here’s the summary of the specs of the Ampere lineup. Keep in mind that none of this info is confirmed, so take it with a grain of salt:
|GPU||Die||Cores||Memory||Memory Speed||Bus Width|
|RTX Titan||GA-102-400||5376||24GB GDDR6X||21Gbps?||384-bt|
|RTX 3080 Ti||GA102-300||5,248||20GB GDDR6X||21Gbps?||384-bt|
|RTX 3080||GA102-200||4,352||10GB GDDR6X||18Gbps?||320-bit|
|RTX 3070||GA104?||2,944||8GB GDDR6||16Gbps?||256-bit|
|RTX 3070 Ti||GA104?||3,072||8GB GDDR6X||16Gbps?||256-bit|