Error when add 2nd psu

[Raffmanlt]

I currently have 6 gpu running on Motherboard that supports 12 gpu
I add 2nd psu, using the psu splitter designed for this. Also new gpu, and riser are powered only by new psu. Only thing hooked same as before is usb cable from motherboard to riser on new gpu.

However it gives me a screen that says turn off immediately and hook up all gpu psie power cables. That's only thing on this screen. I could understand it doing that if I mixed up wires from psu but both power cables for new card are from newly added 2nd psu. Any ideas?

 

[sneekypeet]

Two things that come to mind.....

Are you certain the second PSU is turning on when you power the system?

Is it possible one of the connectors is not clipped all the way into the GPU power plugs?

 

[Raffmanlt]

There have been times 2nd one powered graphics card but it's fans didn't turn on. I will repeat everything again to make sure

 

[Raffmanlt]

So I eventually hooked up gpu to 1st psu and everything was fine. Then I put a different, new gpu on 2nd psu . This time didn't get error msg but all is normal except it doesn't show up in windows. 2nd psu fan turns , fans on gpu turn However. This is using a psu splitter

Additional info: device mngr is normal, no unknown or generic drivers. Also used geforce experience to install latest driver. Made sure no power control settings on any of the gpu. Ran windows update, tried different pcie slot different USB cable and different riser board. My board is capable of 12 connections, 7 of 8 working normally.