What if the motherboard BIOS does not have a "usb-hdd" option?

I have a 320GB mobile hard drive, want to install a WinPE system on the mobile hard drive, but my motherboard BIOS does not have "usb-hdd" option, what should I do?

In fact, most motherboards are supported USB-HDD boot, the key is to set the correct. Different motherboard BIOS options, it is best to find detailed motherboard instructions to follow the settings. The first thing to do is to turn on USB boot device support, such as finding options like "USB Storage Legacy Support" or "USB Storage Function" and setting it to "Enabled." Next If "USBHDD" is not found in the startup type, it may be that the BIOS classifies your mobile hard drive as a normal hard drive, so set the startup type to "HDD" and locate the removable hard drive in the specific boot device list (such as "Hard disk boot Priority") , and set as the preferred boot device.