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There's a real opportunity for AMD here if NVIDIA doesn't release a consumer variant of Volta because Titan X Pascal intentionally cripples FP16 performance to

There's a real opportunity for AMD here if NVIDIA doesn't release a consumer variant of Volta because Titan X Pascal intentionally cripples FP16 performance to drive P100 adoption. It's the same sort of nonsense they pulled with crippling FP64 performance on GTX Titan (Maxwell) to drive K20/K40/K80 adoption, but it got old a long time ago. What's more interesting is the disruptive change to the underlying programming model for Volta (thread-within-thread) that will break a lot of existing CUDA code without refactoring. So if there's no GeForce Volta option, I suspect a lot of that code won't get refactored. So Vega just needs to not suck and to deliver decent TensorFlow/Torch/Caffe performance to succeed as an alternative to NVIDIAopoly.

bmiranda 9y ago
Not having fast FP64 is a design decision. Space isn't free, and FP64 takes up a lot of space that could be used on delivering higher FP32 perf, which is more important for video games.
- varelse 9y ago
  Except that's not how it played out. The Tesla GPU all the way through Maxwell was just a different binning of the GeForce GPU, usually clocked lower for passive cooling and improved stability (sure, K80 is an exception, but K80 is a strange and tragic evolutionary dead-end IMO). Tesla P100 was the first real HW-level divergence with its 2x FP16 support. But because we still can't have nice things, GTX 1080 was the first GPU with fast INT8/INT16 instructions, followed by the mostly identical except much more expensive Tesla P40. So we ended up with the marchitecture nonsense that P100 was for training as P40 is for inference despite being mostly identical except as noted above. I'll assume Volta unifies INT8/INT16/FP16? And I think it's OK if the Tesla card has higher tensor core performance, but if the tensor core on GeForce is slower than its native FP16 support, I can only conclude NVIDIA now hates its own developers and has decided to sniff its own exhaust pipe. Isn't having to refactor all existing warp-level code for thread-within-thread enough complication for one GPU generation? Also, if consumer Volta ends up with craptastic FP16 support (ala 1/64 perf in GP102 vs GP100, slower than emulating it with FP16 loads and FP32 math), NVIDIA will create a genuine opening for AMD to be the other GPU provider in deep learning.

bmiranda 9y ago

Not having fast FP64 is a design decision. Space isn't free, and FP64 takes up a lot of space that could be used on delivering higher FP32 perf, which is more important for video games.

varelse 9y ago
Except that's not how it played out. The Tesla GPU all the way through Maxwell was just a different binning of the GeForce GPU, usually clocked lower for passive cooling and improved stability (sure, K80 is an exception, but K80 is a strange and tragic evolutionary dead-end IMO). Tesla P100 was the first real HW-level divergence with its 2x FP16 support. But because we still can't have nice things, GTX 1080 was the first GPU with fast INT8/INT16 instructions, followed by the mostly identical except much more expensive Tesla P40. So we ended up with the marchitecture nonsense that P100 was for training as P40 is for inference despite being mostly identical except as noted above. I'll assume Volta unifies INT8/INT16/FP16? And I think it's OK if the Tesla card has higher tensor core performance, but if the tensor core on GeForce is slower than its native FP16 support, I can only conclude NVIDIA now hates its own developers and has decided to sniff its own exhaust pipe. Isn't having to refactor all existing warp-level code for thread-within-thread enough complication for one GPU generation? Also, if consumer Volta ends up with craptastic FP16 support (ala 1/64 perf in GP102 vs GP100, slower than emulating it with FP16 loads and FP32 math), NVIDIA will create a genuine opening for AMD to be the other GPU provider in deep learning.