Thanks, but even if the settings in my bios are correct set for OSX I can not even install El Capitan, because of this I asked you if there are other args commands for my MB-CPU-GPU-LAN component model. We created the usb boot based on your video and under windows and on my macbook, is it a secret? must be NVIDIA GPU or Intel to be able to install? and after installing my ATI GPU? what is the secret? I have noticed that I have some settings already in my boot args - are they generic or hardware-based?