nvidia-settings -a [gpu:x]/GPUMemoryTransferRateOffset[3]={value} return blank, no effect

After enabling the cool-bits with nvidia-xconfig, I assigned an offset for memory clock with nvidia-settings:

[gpu:2]/GPUMemoryTransferRateOffset[3]=1000

There’s only an empty line print to stdout, and my GPU’s mem clock isn’t offset? I can manually set the offset clock in nvidia-settings’ GUI though, but I need the CLI option too.
My GPUs include:

gpu:0 and gpu:1 = gtx 1070; gpu:2 to gpu:5 = P106-100

The assignment works for the 1070s but is empty for the P106-100, only gpu:0 has a monitor attached. What’s wrong with it??

Problem solved. P106-100 is a special series made by nvidia for the sole purpose of mining cryptocurrency. It doesn’t have Performance lvl 3, lvl 2 is its max.