A couple of months ago there was some speculation that a priority supply deal between AMD and SK Hynix would prevent NVIDIA from getting its hands on enough HBM2 for the Pascal GPU but those fears were alleviated when news broke about Samsung's HBM mass production plans.
Today Business Korea heard confirmation that both SK Hynix and Samsung will be mass producing HBM2 for NVIDIA's Pascal GPU:
According to industry sources on Sept. 20, Samsung Electronics and SK Hynix are planning to mass produce second-gen High Bandwidth Memory (HBM) for Nvidia's Pascal GPU starting in the first quarter of next year, after completing pilot production and reliability tests by the end of 2015.
Earlier this year, SK Hynix was already supplying first-gen HBM to AMD and Nvidia ahead of Samsung. Micron uses Hybrid Memory Cubes (HMC), a technology similar to HBM, but falling behind it in productivity.