Windows 8 and boot from usb

[3bbb7]

I cant get it working where i boot from a usb.

It works 100% fine on my old computer, but not on this one so I know the usb has it installed right. i have archbang installed with pendrivelinux on it. I go to restart on w8 and hold shift and press restart. this takes me to this screen: except i dont have the USB option.

It worked ONCE before. i tried with linux mint 14 cinnamon installed on the USB and it worked fine. Now I can't get it to work anymore but again it works on my other computer so I know its installed right...

help

 

[loco365]

Have you checked your BIOS configuration to ensure that it checks USB devices?

 

[3bbb7]

How would I do that?

also, it HAS worked before. when I first tried it using mint on my usb it was an option. Then I powered off, tried archbang and the option is gone