Why is my AMD GPU so much slower than Nvidia, despite having more cores?

Message boards : Number crunching : Why is my AMD GPU so much slower than Nvidia, despite having more cores?
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baron_iv
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Message 1889584 - Posted: 13 Sep 2017, 18:55:05 UTC

Does anyone know why a computer with 2 AMD R9 Fury cards (over 7100 cores of yummy goodness) performs WORSE than my slower computer with 2 Nvidia GTX 1070s? For video editing, the 2 Fury cards **destroy** the GTX 1070s, I mean there's not even a contest, the Fury cards complete complex edits and transcodes in a little less than half the time. So why doesn't that pure computational "horsepower" translate into SETI@home? Is it just because the AMD side isn't getting the same love that the NVidia gets from the programmers?

For reference, my Fury cards have 3584 cores each, and I have two. The Nvidia 1070s have 1920 cores and I also have two of those. Is CUDA just more efficient than OpenCL? I'm basically just burning power, as far as SETI goes and I'd be FAR better off if I bought a single Nvidia GTX 1080Ti, in terms of power usage and SETI results crunched.
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Profile Keith Myers
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Message 1889597 - Posted: 13 Sep 2017, 19:40:32 UTC - in response to Message 1889584.  

From looking at your systems, you are not comparing apples to apples. More like apples to oranges since the Nvidia computer is running the Linux special app and the ATI computer is running the standard SoG app. If there was a "special" linux version app for the ATI cards, they likely would be comparable.
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Message 1889613 - Posted: 13 Sep 2017, 20:37:35 UTC - in response to Message 1889597.  

From looking at your systems, you are not comparing apples to apples. More like apples to oranges since the Nvidia computer is running the Linux special app and the ATI computer is running the standard SoG app. If there was a "special" linux version app for the ATI cards, they likely would be comparable.


Why isn't there a "special" app for AMD?
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Message 1889615 - Posted: 13 Sep 2017, 20:41:36 UTC - in response to Message 1889613.  

Probably because Petri (the developer of the special app) doesn't have or use ATI cards. You probably should ask over in the specific thread for the special app.

Linux CUDA 'Special' App finally available, featuring Low CPU use
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rob smithProject Donor
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Message 1889617 - Posted: 13 Sep 2017, 20:43:47 UTC
Last modified: 13 Sep 2017, 20:43:57 UTC

Adding to that, the nVidia+CUDA combination does appear to be much more amenable to the sort of optimisation than the OpenCL+AMD combination.
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Grant (SSSF)
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Message 1889700 - Posted: 14 Sep 2017, 7:06:30 UTC - in response to Message 1889584.  

Does anyone know why a computer with 2 AMD R9 Fury cards (over 7100 cores of yummy goodness) performs WORSE than my slower computer with 2 Nvidia GTX 1070s? For video editing, the 2 Fury cards **destroy** the GTX 1070s, I mean there's not even a contest, the Fury cards complete complex edits and transcodes in a little less than half the time. So why doesn't that pure computational "horsepower" translate into SETI@home?

For the same reason the Nvidia cards do so poorly with video editing- the software isn't as optimized for that particular architecture/ compute platform. Get someone that knows what they're doing to optimise the video editing software to take advantage of the GTX 1070s, and the video editing performance situation could quite easily be reversed.
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Message boards : Number crunching : Why is my AMD GPU so much slower than Nvidia, despite having more cores?


 
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