DRAM and NAND flash giant Micron Technology has begun sampling its next-generation GDDR5X memory chips to customers. The company is ready with chips in the 8 Gb (1 GB) and 16 Gb (2 GB) densities, making it possible for GPU makers to build graphics cards with 8 GB and 16 GB total onboard memory, respectively, over a 256-bit wide memory bus, by using just one chip per 32-bit channel.Apart from 8 Gb and 16 Gb densities, Micron's GDDR5X chips offer GPU makers a transition from GDDR5 with minimal engineering, since the standard has similar electricals to its predecessor, and a similar BOM structure; while offering up to double the clock speeds to GDDR5, and running at a lower voltage of 1.35V. Both AMD and NVIDIA have reportedly expressed interest in building graphics cards with GDDR5X.