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Comment by n00b101 | Hacker News Reader

> Apple is using one of AMD’s "Polaris" graphics chips

Huge disappointment. MacBook Pro used to have NVIDIA GPUs and was an excellent CUDA development environment. They switched to AMD around 2012. I suspect the change was more business related than technical.

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Apple was a huge investor into OpenCL. AMD is as well. AMD supports OpenCL 2.0 while NVidia folks are stuck on OpenCL 1.2.

I recognize that a lot of people want CUDA instead, but OpenCL support is superior on AMD cards.

My Nvidia card reports OpenCL 1.2 support: http://i.imgur.com/nzb7OL5.png

AFAIK their OpenCL debugging/profiling tools are still terrible compared to CUDA or AMDs OpenCL though.

Ahhhh... damn it. I got the version numbers screwed up.

NVidia supports 1.2. AMD supports 2.0. Same concept, but I got the numbers all jumbled up. I'll edit the above post for the correct numbers.

http://support.amd.com/en-us/kb-articles/Pages/OpenCL2-Drive...

http://stackoverflow.com/questions/29219307/opencl-2-0-on-nv...

(Hard to "prove a not", so I'll just leave the Stackoverflow page here)

nVidia is way better than AMD at software: CUDA, DX11 drivers et cetera. For stuff that has much less room for software optimization, AMD tends to be very competitive: DX12, Vulkan, OpenCL.

But this time around Apple is writing their own software (Metal). So this time around it's not surprising that Apple doesn't want to pay more for superior software if it's not going to use the software. It sucks for CUDA users, but Apple doesn't care about you.

AMDs Polaris architecture is also much more power hungry than NVIDIAs Pascal architecture, at least on the desktop variants we've seen so far.

The RX480 (Polaris) trades blows with the GTX1060 (Pascal) performance-wise, but the 1060 uses about 30% less power at load:

https://www.techpowerup.com/reviews/NVIDIA/GeForce_GTX_1060/...

Well the OP's quote continues with "because the design offers the power efficiency and thinness necessary to fit inside the slimmer Apple notebook". It's not like Apple would just ignore power efficiency.

The RX480 Polaris is about 30% faster than the GTX1060 running DOOM4/Vulkan. Apple's Metal is very similar to Vulkan, so it's quite possible that nVidia Pascal and AMD Polaris have similar power usage while using Metal.

Doom 4 is an outlier, the RX480 doesn't consistently gain that much from Vulkan or DX12. You could just as easily point to Tomb Raider DX12, where the 1060 beats the 480 by about 20%.

According to Guru3D the two cards perform almost identically in Ashes of the Singularity and Total War: Warhammer, both AMD-sponsored DX12 games.

Tomb Raider doesn't use async compute.

And whether Doom 4 is an outlier or just an example of the difference between Vulkan and DX12 is yet to be determined.

My conjecture is that the big difference between Vulkan and DX12 is that nVidia has put more of it's driver engineering magic into DX12 than it has into Vulkan.

Metal won't have that nVidia driver engineering magic, so I believe that DOOM4 is the best benchmark we have of performance and power consumption for Metal. But one benchmark can be misleading for a wide variety of reasons.

Tomb Raider had async compute implemented for GCN and Pascal in a post-release patch, and benchmarks on that patch still pegged the 1060 as ~20% faster than the 480:

http://www.eurogamer.net/articles/digitalfoundry-2016-nvidia...

And conversely, the developers of Doom said their async path is currently only tuned for GCN and will be enabled on Pascal in a future patch.

We've seen from 3DMark Time Spy that Pascal does benefit from async compute, so there's performance being left on the table there.

Honestly doesn't matter when one can't run CUDA and almost all the pro applications for a GPU are CUDA based.

Plus, AMD isn't as good for Linux, if you end up putting that on the machine instead of (or alongside) OS X.

The 2013 and 2014 macbook pro still had NVIDIA (fortunately! AMD has always given me trouble)

it's still better than the intel integrated video all but the top of the top of the line macbook pros got saddled with.

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