The Graphics DRAM Design Center in Munich, Germany recently received the first functional devices. And not only were they ready sooner than anticipated, they're also performing very well. The early GDDR5X components are capable of hitting data rates of 13Gbps, which is on the high end of the intended 10-14Gbps range for GDDR5X memory. The first-generation GDDR5X is a 8Gb (1GB) memory chip made on 20nm process technology.
The JEDEC specification for GDDR5X was published in January. In addition to utilizing a number of proven features from the GDDR5 specification, GDDR5X incorporates a number of new features to meet the demands of next-generation, high-performance graphics systems. With first components becoming available, it is now proven that QDR mode is the path to achieve the industry’s fastest data rate (13Gbps and higher) on a discrete memory device.Micron is ramping up production and expects to start its sampling process later this spring. Full volume production is slated for this summer and based on the performance of the early samples, Kido estimates GDDR5X definitely has potential to hit speeds of 14Gbps and potentially beyond.
Compared to GDDR5, these ultra-high data rates were achieved at an improved power consumption per transmitted bit due to VDD/VDDQ of 1.35V, while not gating maximum speed of the device. We also added features to improve system signal integrity: a new package with reduced ball pitch enables shorter PCB traces, which improves electrical performance.
According to the rumor mills, AMD and NVIDIA are planning to use GDDR5X memory as a lower-cost alternative for the expensive HBM2. The latter will be used for flagship products, whereas GDDR5X may be used for high-end cards like the GP104, the GeForce GTX 980 successor. Given that Micron confirmed it won't be able to mass produce GDDR5X before summer, these cards are still many months away from us.