GBs are notoriously 'picky' about USB devices in general, and pendrives in particular:
http://www.tomshardware.com/forum/ [...] 5-problemo
http://www.tomshardware.com/forum/ [...] abyte-tale
That said, if it will work at all, you need to -
on the "Integrated Peripherals" page of your BIOS:
"USB Controller" to "Enabled"
"USB 2.0 Controller" to "Enabled"
"Legacy USB storage detect" to "Enabled" -
only when, on the
next boot, you intend to
either use a USB stick
from the BIOS (CMOS parameter set storage, BIOS flashing), or
boot from one - if left enabled at other times, has a propensity to trigger 'boot-loops'...
on the "Advanced BIOS Features" page of your BIOS:
one of "First/Second/Third Boot Device" set to "USB-HDD"
Alao, for a lot of systems, your flash drive needs to be formatted to FAT32 before putting boot files on it...
HP USB Disk Storage Format Tool - v2.1.8 here:
http://files.extremeoverclocking.com/file.php?f=197