Just trying an experiment with Lc0.
To use two graphics cards, should they be set to run in SLI or independently?
Thanks
Two GPUs
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Re: Two GPUs
SLI has only effect for rendering graphics in video games,
so you do not need to set up SLI for Cuda or OpenCL.
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Re: Two GPUs
You must choose which GPU to use, or both, gpu=0 is for the first GPU and gpu=1 the second, for example in Cutechess
-engine name="Lc0201_32644" cmd="lc0.exe" option.Threads=4 nodes=8000 option.Backend=multiplexing option.BackendOptions="(backend=cudnn,gpu=0),(backend=cudnn,gpu=1)"
for use both GPU in Arena you must set:
Backend: Multiplexing
BackendOptions: (backend=cudnn,gpu=0),(backend=cudnn,gpu=1)
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Re: Two GPUs
For the RTX cards presumably it'd look like this:Javier Ros wrote: ↑Fri Jan 18, 2019 12:04 am
for use both GPU in Arena you must set:
Backend: Multiplexing
BackendOptions: (backend=cudnn,gpu=0),(backend=cudnn,gpu=1)
Backend: Multiplexing
BackendOptions: (backend=cudnn-fp16,gpu=0),(backend=cudnn-fp16,gpu=1)
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Re: Two GPUs
YesWerewolf wrote: ↑Fri Jan 18, 2019 9:46 amFor the RTX cards presumably it'd look like this:Javier Ros wrote: ↑Fri Jan 18, 2019 12:04 am
for use both GPU in Arena you must set:
Backend: Multiplexing
BackendOptions: (backend=cudnn,gpu=0),(backend=cudnn,gpu=1)
Backend: Multiplexing
BackendOptions: (backend=cudnn-fp16,gpu=0),(backend=cudnn-fp16,gpu=1)
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Re: Two GPUs
What is the difference in these two parameters ??Javier Ros wrote: ↑Fri Jan 18, 2019 10:00 amYesWerewolf wrote: ↑Fri Jan 18, 2019 9:46 amFor the RTX cards presumably it'd look like this:Javier Ros wrote: ↑Fri Jan 18, 2019 12:04 am
for use both GPU in Arena you must set:
Backend: Multiplexing
BackendOptions: (backend=cudnn,gpu=0),(backend=cudnn,gpu=1)
Backend: Multiplexing
BackendOptions: (backend=cudnn-fp16,gpu=0),(backend=cudnn-fp16,gpu=1)
I do have an old pc with an old GTX 690.
It has 2 gpu cores.
I tried the first parameters and it looks like then both gpus are running 100 %.
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Re: Two GPUs
These parameters are for two physically different cards, on a motherboard that supports two PCIE slots.mclane wrote: ↑Fri Jan 18, 2019 8:11 pmWhat is the difference in these two parameters ??Javier Ros wrote: ↑Fri Jan 18, 2019 10:00 amYesWerewolf wrote: ↑Fri Jan 18, 2019 9:46 amFor the RTX cards presumably it'd look like this:Javier Ros wrote: ↑Fri Jan 18, 2019 12:04 am
for use both GPU in Arena you must set:
Backend: Multiplexing
BackendOptions: (backend=cudnn,gpu=0),(backend=cudnn,gpu=1)
Backend: Multiplexing
BackendOptions: (backend=cudnn-fp16,gpu=0),(backend=cudnn-fp16,gpu=1)
I do have an old pc with an old GTX 690.
It has 2 gpu cores.
I tried the first parameters and it looks like then both gpus are running 100 %.
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Re: Two GPUs
I am also thinking of setting up 2 GPU's for LC0. So is this code to be added to the .dll files? How do you get Leela to use both GPU's on CB GUI? Just install the UCI engine and add an edited .txt file?
How about if you do setup in SLI, will LC0 consider 2 x GPU's as one GPU if SLI or Crossfire is used?
How about if you do setup in SLI, will LC0 consider 2 x GPU's as one GPU if SLI or Crossfire is used?
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Re: Two GPUs
M ANSARI wrote: ↑Sat Jan 19, 2019 8:24 am I am also thinking of setting up 2 GPU's for LC0. So is this code to be added to the .dll files? How do you get Leela to use both GPU's on CB GUI? Just install the UCI engine and add an edited .txt file?
How about if you do setup in SLI, will LC0 consider 2 x GPU's as one GPU if SLI or Crossfire is used?
I do not know the answer to the last question.
No SLI required, no txt file, in Chessbase you must only Create UCI Engine,
in Parameter, you must set Backend to Multiplexing and in BackendOptions you must write
(backend=cudnn,gpu=0),(backend=cudnn,gpu=1)
It is advisable to add to the name the version 32xxx and set Priority to Below Normal (recommended for all engines)
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Re: Two GPUs
SLI and Crossfire are only used for generating graphics, Cuda and OpenCL con not use these.
SLI was introduced with the Vodoo 2 3D-accelerator cards by 3dfx,
the technique splits the graphics workload across the gpus,
imagine that one gpu renders only the odd frames and one gpu renders only the even frames.
https://en.wikipedia.org/wiki/Scalable_Link_Interface
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