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I'm trying to install Ubuntu 12.10 for the first time. I've downloaded the 64-bit torrent from ubuntu.com and have created a bootable USB using Unetbootin. When I entered the BIOS and booted from USB, it gave me the options to try Ubuntu, install it and some others. I've tried both, but my result is the same. The computer displays a black screen and nothing seems to happen. The computer currently has Windows 8 on it.