w7218 can't boot from usb

Hi there,
I've been using my easynote w7218 for almost 2.5 years now, and it has served me well. One thing that drives me crazy is; the boot menu does not contain any options for booting from usb.
If I forget an external usb disk plugged in however, the computer rarely boots, it usually gets stuck. So it can see usb port during boot, but cant' boot from it? I've created a live usb stick which worked just fine in other computers, buy my laptop does not care about it. Actually it waits for a couple of seconds, shorter compared to getting stuck forever if there is a usb drive plugged, than it moves forward with the normal boot sequence from hd.
I'd love to hear any clues, if you know any. Can I boot from usb? Even packard bell support faq says that the devices in w series get stuck since they are trying to find a boot device in usb. So why it can't boot when there is one inserted???

Kind regards
Seref Arikan