Hi guys. About a month ago I bought these GPU's and components to start mining:

1x Asus Turbo GTX 1080 - 8Gb
2x Gigabyte Turbo GTX 1080 - 8Gb
2x MSI GTX 1050Ti - 4Gb

Motherboard Asus z170 Pro Gaming Aura
1x PSU EVGA 850 BQ.
CPU Intel Pentium G4400
SSD Kingston UV400 - 120 Gb
1x RAM Kingston HyperX Fury DDR4

Under Windows 10, I have succeeded in getting 4 GPU's to work fine. But I have not succeeded to run more than 4 GPU's. I've already check the raisers, Changing Gen1, Gen2, Gen3, Adding another PSU (Corsair CX 650M), Enable Above 4G decoding. And nothing seems to work.

- - ->> When I boot the rig with 5 GPU's, the Asus logo show up, then a black screen, and nothing else happen. <<- - -

I read in other post that the solution is to increase TOLUD to 3Gb instead of Auto. The thing is that I can't find the TOLUD option on Bios.

So, How can I change TOLUD on Asus z170 Pro Gaming Aura?.
If anyone could run more than 4 GPU's on this Motherboard, please share the settings.

Thanks in advance for your help!
Have a great day