El capitan install. Won´t boot to OSX

El capitan won´t install.

After downloading the el capitan in OSX Lion and the installer told me to restart the machine, the macbook is going in a complete freeze when the bar is.

The computer does NOT respond to command-R, so I can´t erase the disk that way. I´ve also tried to run the el-capitan-installer with an USB-drive from ALT, but that one is also stopping in exact the same position on the bar above. NVRAM etc has been reset 1476 times. The safemode does not help either, it just boots again and again with only seconds between every boot. So, now I feel like I´m caught in Inception, with no possibility to go either back or forward.

I´ve searched forums to find someone with the same problem, but haven´t found it yet. Anyone?