Using 2 x GTX 1070 on Ubuntu 20.04.1 LTS. Only 1 gpu is active.
System Ryzen 7 3700X, Taichi X570 (SLI) motherboard dual GTX 1070 with Nvidia HB bridge.
SLI works perfect under Windows I do not think it is hard ware, I think I have made a mistake some where and am having a huge difficulty finding it.
NVIDIA(0): Invalid SLI option: 'On'; using single GPU rendering
From nvidia driver changelog:
2020-09-17 version 455.23.04
* Removed support for the SLI modes "SFR", "AFR", and "AA". SLI Mosaic,
Base Mosaic, GL_NV_gpu_multicast, and GLX_NV_multigpu_context are still
supported.
So there’s no real SLI auto-multi-gpu-rendering anymore wth Linux unless the application uses the mentioned gl methods.