Comment by dogma1138 | Hacker News Reader

Comment by dogma1138 | Hacker News Reader

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>First off not sure what you are referring to by "Maxwell 1" and "Maxwell 2"; there's GM204, GM206, GM200 all very similar, and GM20B the slight outlier.

GM1XX is Maxwell 1st Gen, which was the 750ti, the Gefore 800M series, Tegra K1 and Tesla M10, GM2XX is Maxwell 2nd Gen.

>Not really. In Kepler they experimented with the SP/DP balance a bit (1/3), in Maxwell they were pushed by 28 nm, in Pascal they returned to the DP = 1/2 SP throughput

Maxwell wasn't 1/3 it was 1/32 (no this isn't a typo) ;) this is the same (or even worse IIRC it's 1/64 now) with Pascal with the exclusion of the GP100, the Pascal Titan and Quadro cards are 1/32 or 1/64.

As I said NVIDIA keeps this for very limited silicon if you buy a desktop/workstation GPU even with Pascal don't expect DP/HP performance.

As for the big players, yes they are trend setters but they are also can easily turn into "blackmailers" if you have a single client which buys half your GPU's they dictate the terms, companies went under because of contracts that take too much of their delivery pipeline.

> GM1XX is Maxwell 1st Gen, which was the 750ti, the Gefore 800M series, Tegra K1 and Tesla M10, GM2XX is Maxwell 2nd Gen.

My bad, forgot about 5.0 devices being called GM1xx. Still, AFAIR there was little practical difference (in particular instruction set) between all but the compute capability 5.3 Tegra.

> Maxwell wasn't 1/3 it was 1/32 (no this isn't a typo) ;) this is the same (or even worse IIRC it's 1/64 now) with Pascal with the exclusion of the GP100, the Pascal Titan and Quadro cards are 1/32 or 1/64.

I did not say Maxwell had 1/3 DP flop rate, I said Kepler had that, but Maxwell was pushed by the 28 nm process (so they had to get rid of all DP ALUs).

> As I said NVIDIA keeps this for very limited silicon if you buy a desktop/workstation GPU even with Pascal don't expect DP/HP performance.

Never disagreed, but they can only do that because their professional compute division has grown big enough that it it worth designing different silicon; that shift happened in fact after Kepler, GK110 was more or less the same on GeForce and Tesla (e.g. 780 Ti and K40). They're also trying to find a good way to do market segmentation and DP ALU die area is an obvious candidate to play with. Still, no HP on GP102/104 is a curious thing, especially as the Tesla P4/P40 that oficially target ML/DL would really need it. My bet is they won't "forget" HP on lower-end Volta; not all consumer chips will support it, but unless they'll design different dies for GV102/104 (or whatever they'll call the non-DP Tesla uarch), which I doubt, some desktop parts will also support it.

NVIDIA said they have a new double precision silicon for Volta so in effect "DP" should become the new base unit, which would either give you 1:1 DP/SP or 1:2 DP/SP if they can 2 SP operations on a single DP unit, but no much talk about HP. The emphasis on DP performance across the board was extreme with NVIDIA this time around, which makes me wonder if they think FP16 is irrelevant for some reason.

As for Kepler well it had 1:3 but only on few chips, most kepler based GPU's had 1:24 DP performance, the 780ti had 1:24 while the Kepler Titan had 1:3, the Titan Black then had 1:24 again and again no one seemed to care...

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