It got a bit buried in the Computex shuffle, but at the beginning of the month Micron posted a blog entry laying out in broad strokes the company's plans for graphics card memory. The big news in the piece is that the company has managed to get its GDDR5X memory running at 16 Gbps in a lab scenario. Micron also says it will have functional GDDR6 silicon "very soon."
Regarding the GDDR5X news, the company says that the extremely high speeds were achieved using "a meaningful sample size" of its mass-production GDDR5X memory. That means that these results aren't simulated or using exotic silicon. The observation was made inside a testing facility, though, so don't get too excited yet—it's not likely we'll be seeing GDDR5X at 16 Gbps on graphics cards anytime soon.
The post provides a few interesting details about GDDR6 and how it differs from GDDR5X. Notably, while GDDR5 is typically configured with 16- or 32-bit-wide I/O, GDDR6 will support two 8- or 16-bit-wide channels. Micron doesn't explain what the benefits of such a configuration are, but we can speculate that a reduced-power single-channel mode could be useful in mobile devices. GDDR6 also uses a larger package than its predecessor despite having ten fewer contacts. Micron notes that the distance between contacts is slightly greater as a result.
Unfortunately, we probably won't be seeing GDDR6 in actual products for a while. Micron's Kris Kido says that the company expects to have the new memory in production by "early 2018." That would imply that graphics cards with the new chips onboard aren't likely to show up until late next year at the earliest.
Looking back almost two years ago to the launch of the Radeon R9 Nano, it seemed like HBM might really shake things up. At this stage, that hasn't really been the case. The technology itself isn't at fault; the benefits are real. One would guess that the reasons why HBM isn't more widely-used are related to supply and pricing. High-speed GDDR memory may not have the power-consumption or space-saving benefits of HBM, but at least the performance is there. These are interesting times for the high-speed memory market, and we're very curious to see what lies ahead.