USB Boot option gone missing

Hello all, thanks for looking. I am working on a dell inspiron 1318, just installed Ubuntu and BT5 from a usb stick a couple of days ago. Today i was starting to install Arch and the option to boot from USB has disappeared from my list of options. I checked in Bios and it is still listed as a boot option. I thought i would check here before i did anything rash, but i am not seeing anyone with the same problem. I am about to make USB the only way to boot but i feel like that is not going to work. Has this ever happened to anyone else ?

Thanks in advance

GPGPNYC