The Hot Chips conference is going strong in Cupertino, California, and the first juicy tidbits of information have started popping up from folks at the event. According to sites reporting from the conference, SK Hynix and Samsung talked about the new generation of High-Bandwidth Memory, aptly called HBM3.
HBM3 improves on the current-generation HBM2 in nearly every regard. It'll use dies with higher capacity and bandwidth. Each die should now pack 16Gb (2GB) per layer, meaning it's possible we'll eventually see graphics cards with up to 64GB of HBM3 on board. As a point of reference, Nvidia's Tesla P100 accelerator currently uses just 16GB of HBM2. The bandwidth increase is impressive, too: there'll be at least 512GB/s per package on tap (up from 256 GB/s), which translates into a potential aggregate bandwidth in the range of terabytes per second.
There are power savings on offer, too, as HBM3 purports to offer a "much [lower]" core voltage than HBM2's 1.2V. Ars Technica notes that both Hynix and Samsung are already at work on the new memory type. There's no fixed date for mass production yet, but Samsung expects to produce the memory in volume between 2019 and 2020.
While high-end HBM is interesting, it also adds a hefty price premium to any product that includes it. Samsung has a couple alernative in the works, though. The company unveiled its plans for a mass-market "low cost HBM," a variant of HBM2 with a comparatively lower bandwidth of 200 Gb/s per die, but with a pin speed of approximately 3 Gb/s. (HBM2 tops at 256 Gb/s per die.) Samsung says this memory type will come at a fraction of the price of HBM2, thanks to the removal or reduction of features like ECC, buffer dies, and TSVs (through-silicon vias).
That's not all, though. Samsung also predicts it will begin mass production of GDDR6 (the successor to GDDR5X) come 2018. This memory type should offer 14 Gb/s per die, slightly up from GDDR5X's 12 Gb/s, as well as lower power consumption. It should be noted, though, that GDDR5X chips in current-generation graphics cards don't run anywhere close to that theoretical 12 Gb/s limit yet, though, so there's no telling what the effective speed of GDDR6 will be.