I have a Sony Vaio SV-E14A2M1E with Win 8.1; and I just created a bootable USB with Linux mint 17.1, but I can't boot from it. I've done a bit of research, but I'm not sure with what I've found.
As you already mentioned you're using W8.1
Some things you might have a look at:
- General Problems / Usage for (Linux)/Ubuntu with newer hardware-> UEFI Troubleshooting
try this solution it may fix your issue: bootable usb using cmd