The latest JEDEC standards for high-bandwidth memory (HBM2) allows for 24GB rather than 8GB of memory, as well as speeds of up to 307GB per second, per stack. This effectively increases the amount of memory NVIDIA or AMD can put on a single HMB2 card to as much as 96GB, with bandwidths of 1.2 TB per second.
https://www.notebookcheck.net/New-JEDEC-standard-increases-HMB2-memory-limit-from-8GB-to-24GB.383466.0.html