I have a 16GB USB 3.0 memory card, Lexar. I've used the MS usb/dvd tool to make it bootable. Downloaded 64bit of the W8 Release CP iso. I set my bios to boot in this priority
USB HDD
USB FDD
HDD
I have a Samsung Series 9 ultrabook, NP900X3B-AO1US
I've used the same MS tool, same USB...