max number of GPUs on linux

I’m running ubuntu 16.04.3 - whats the max number of GPUs per system?

This 2016 thread: https://devtalk.nvidia.com/default/topic/893533/cuda-setup-and-installation/nvidia-driver-crash-on-32-gpu-linux-system/post/4720347/ says max is 16 GPUs.

Is 32 GPU system now possible?