Recently I explained how you can test if your computer supports booting from USB device. So, if it is not compatible with USB booting, what should you do? Don’t worry, you can still boot from USB even if your computer’s BIOS do not support it!
Boot Computer From USB Device Without Bios Support for USB Booting
First, download Plop Boot Manager. Install it on your hard drive or burn its image on CD/DVD. Then boot into Plop Boot Manager from the respective device. On booting via Plop Boot Manager, you will see its own menu which lets you choose the device from which you want to boot. And this list include USB booting as well. Thus, using this method you can boot from a USB device irrespective of whether your computer’s BIOS supports it or not.
Plop Boot Manager comes with USB drivers built-in and it can be used to access USB device of size up to 2TB, even if the BIOS supports only 128MB.