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I recently bought a Toshiba Satellite P50, I tried installing Ubuntu 12.04.3 and 13.10 alongside Windows 8.1.
If I disable Secure Boot, but leave the UEFI mode on, I can get to the screen that asks If I want to try Ubuntu. When I select that option the screen just goes black and nothing happens.
I'm only able to load Ubuntu from a usb when the Secure Boot and the UEFI mode are both enabled. But, after I install it, the computer loads only into Windows. I ran the boot-repair after from the usb, after disabling Secure Boot, and it told me that I should disable Secure Boot, but when I did I was again unable to load it from the usb.
Thanks for taking the time to read this. Any help or suggestions with would be greatly appreciated!!