will it boot from a live dvd?
did you try your bootable usb in any other computers to make sure it works ok?
when you went into bios did you change the boot order to boot usb first?
seems weird but i have seen a few modern laptops that do not like bootable usb, thats why i tend to just buy a cheapo second hdd and run off that..my password lists and hash tables are too epic for thumbs


