- "UEFI OS" boot options spawn like rabbits and crowd the BIOS of my Win10/ElCapitan dual boot Hackintosh until the system won't boot past the POST screen, only disconnecting drive fixes problem. Why does this happen, how can I prevent it? http://www.tonymacx86.com/el-capitan-desktop-guides/172672-unibeast-install-os-x-el-capitan-any-supported-intel-based-pc.html 14 comments techsupport