Bios for Asus Z77 Mainboards to be able to accept 12 GPUs attempt

Hi.
I tried this last days very hard to get on Asus z77 chipset mainboards 12 gpus running.
With the default Bios you are able to run 6 Gpus

With some modifications in Amibcp 4.5 I can get to run 8gpus:
Allowed most hidden menus to be seen by the user and changed then in Bios:

  • Above 4g decoding: enabled
  • CMS Disabled
    With this I am able to run 8 Gpus.

Now comes the thing. I tried some more settings but never got more than 8 Gpus running.
I use the typical mining USB risers to connect more GPUs.

I have an B75 BTC Mainboard form AliExpress. That gives me hope. Because there somehow it is possible to run 12 GPUs. Same generation of hardware. Maybe that helps with finding what has to be modified to enable 12 GPUs on the ASUS z77 mainboard.

Right now, I’m trying on the Sabertooth Z77. But have also tried on the Asus p8z77-v Deluxe board

is there somebody that can lead me to the right path maybe, or helping with modified Bios.
Thanks in advance

Link to Asus Sabertooth Z77 and B75BTC Aliexpress bios
https://drive.google.com/file/d/1dYj_b4KYPxrQQDyKYB4WiQhXAkXkvyXT/view?usp=sharing