CI bus ID and GPU ID

I have 3 graphics cards installed on Ubuntu 16.04, and when I checked the PCI bus IDs by using three different commands;

1. nvidia-smi,
2. lspci | grep VGA, and
3. nvidia-settings

1) and 2) gave the same IDs, but 3) gave different IDs.
It turned out that 3) was correct, which worked fine for another program while the others didn't. I was wondering why they gave different bus IDs in the first place.

Another problem was GPU IDs (0, 1, 2), where none of the GPU IDs reported were correct (commands 1)/2) and 3)), and I had to find the correct IDs by trying random combinations. Below are the screenshots of a), b), and c).

(a) nvidia-smi(b) lspci(c-1) nvidia-settings_GPU0(c-2) nvidia-settings_GPU1(c-3) nvidia-settings_GPU2

Can anyone help me?

1 Answer

nvidia-smi and lspci display hexadecimal values.nvidia-settings displays decimal values.

xorg.conf takes decimal values, that's why nvidia-settings seemed the correct one.