I think the rumours might actually be true that this is maxwell with tweaks. The resulting performance is due mostly to massively increased clocks from the new manufacturing process and a small increase in shader count over the 980.
So far nothing about new dx12. But I'm just at the VR audio thing. The couple features I have heard so far are software, something they can put on maxwell as well. And that audio thing is just catching up to AMDs trueaudio.
They can't put those into Maxwell.
1. Maxwell uarch does not support instant graphics <-> compute workload switch. The entire SMX/CU either does graphics or compute. If it's doing graphics and needs to switch to compute, it has to flush and wait for full idle before starting the compute task.
2. Maxwell uarch is incapable of interrupting a graphics task in flight for a compute task on priority (fine-grained preemption). It has to wait for the graphics task to finish, then flush/idle, switch to the compute workloads. Because of this, it is incapable of async timewarp for VR, if you move your head often, the async timewarp on priority preemption will get stuck behind a current draw call and does not trigger at the time it needs to.
I said this several times for awhile now, some folks used to not believe me, but it's what NV have been saying in their programming guide & dev blog since late 2014.
The new VRWorks features are Pascal only.
Pascal is Maxwell made to be GCN-like, running at very high clocks due to TSMC's 16nm FF node. It's still missing multi-engine (ACEs), but Async Compute usage will not cause a performance loss on it due to #1. Volta I think will have a multi-engine design. Late 2018 when by then I hope advanced DX12 games will be the norm.