Suggested settings for 2x ASUS 2080 SUPER OC

[Nordlandia]

2x ASUS GeForce RTX 2080 SUPER ROG Strix OC in NVlink. 

Can i use TCEC settings for Lc0 or CCC without worrying to much about possible performance increase/decrease.

Inputs will be appreciated. Thanks. 

[Cary Knoop]

Start with something like this:

lc0.exe  --minibatch-size=512 --max-prefetch=64 --max-collision-events=128 --backend=multiplexing --backend-opts=(backend=cudnn-fp16,gpu=0),(backend=cudnn-fp16,gpu=1) --threads=4

[Nordlandia]

Are you sure 4 threads is ideal over 3? 

In my i7-5960X 4.5GHz 2080S OC use about 1.5 Core under load. 

[Cary Knoop]

Actually it depends on your configuration.  

With two similar GPU's it is best to run using the 'roundrobin' backend and in that case, it is best to run with 3 or 4 threads.  Four threads will give you more nodes per second but due to MCTS, you may wind up wasting computing cycles, so three may be the best option.

If you have more than two similar GPU's you should run the 'demux' backend and use only two threads, there would not be any need for more than two threads.

In cases where your GPU's are dissimilar, it is best to run the multiplexing backend because both for the 'roundrobin' and 'demux' backend all GPU's have to wait till the weakest GPU is done.

 

[Nordlandia]

Thanks for the detailed explaination Cary Knoop. 

So with two identical cards:

ASUS GeForce RTX 2080 SUPER ROG STRIX OC

It's best to opt for roundrobin than demux ? 

[Cary Knoop]

Yes

[Nordlandia]

TCEC GPU server consists of: 1 x 2080 ti + 1 x 2080 so multiplexing is used as previosuly explained. 

CCC use demux because of very strong server with powerful GPUs.