5 GPU's on Windows 7?

have 5 AMD R9 380
Windows 7
ASUS SABERTOOTH Z77

Trying to get the 5th GPU to work no joy.
Found this link in forum but not much discussion about it after it was posted?
https://lbr.id.lv/6xgpu_mod/6xGPU_mod.html

Any help or advice would be great thanks,