German tech site 3D Center dug up details about the codenames of some of NVIDIA's upcoming Pascal and Volta GPUs. The information originates from references in a CUDA dll file from one of NVIDIA's latest drivers, mixed with a healthy dose of speculation.
GP100 - Enthusiast chip, replaces the GM200. Earlier reports pointed to 17 billion transistors, 4096-bit memory bus, up to 16GB HBM2 and twice the performance/Watt than its predecessor.
GP102 - No details known but the codename suggests it's a high-end GPU.
GP104 - High-end chip, replaces the GM204
GP106 - Performance series replacement for the GM206
GP107 - Mainstream class replacement for the GM107
GP10B (or typo for GP108?) - Low-cost successor for the GM108 chips
GV100 - Future enthusiast chip that will replace the Pascal-based GP100. Earlier rumors pointed to double the performance/Watt, up to 64GB memory, probably made on 10nm process