AMD was the first graphics card company to make use of HBM (high bandwidth memory) with their release of the Fury X and Fury graphics cards. NVIDIA has stated that they are waiting for the second iteration of HBM (HBM2) before they move over to the standard. According to a recent report AMD could be leveraging their deal with SK Hynix to get priority access to HBM2 for their next graphics card series (Arctic Islands).
HBM1 is currently available in 4GB capacities with speeds of 512 GB/s. HBM2 will increase these numbers to 16/32GB and over 1024 GB/s. Just like we’ve seen with HBM1, HBM2 will have very low yields at launch, so expect there to be a very limited supply available. If AMD does have the exclusive for the first wave of HBM2 it could mean that NVIDIA won’t be able to use HBM2 until the yields improve.
NVIDIA plans to release their Pascal architecture in 2016 and it could be designed for either GDDR5 or HBM2. If they can’t get a hold of enough HBM2 they would have to go the GDDR5 route and then do a HBM2 refresh later on. This could cause NVIDIA to lose market share over AMD, only time will tell.