Using common MSI Z270-A Pro + Celeron G3900 + 4GB RAM +3 x PCI-E Switches (9 GPU's connected to switch and 3 GPU direct to motherboard). Power Subsystem - two HP common slot PSU 1200W + 160W Pico PSU (for motherboard and switches)
Sorry for bad photo and my English)

Thats an impressive rig you have there, esp with success in getting 3 splitters working.