Change core voltage on a 1050 Ti on Linux

Hi guys,

I recently bought a GeForce GTX 1050 Ti and use it on Linux. But there’s one problem I have:
It seems I’m unable to change the voltage of my graphics card, although I set the Coolbits option to 28. I can overclock the GPU fine, but I can’t find the voltage setting. Is there a way to achieve this?

Thanks in advance,
Oebbler