Booting from USB sticks... which one?

Kind of odd question.

Lets assume - reasoning aside for the moment - that I've formatted 2 USB flash drives as bootable drives, and I've got both plugged in at the same time. I've got USB drives set as bootable in BIOS.

Which USB drive will I boot off of? Is there a way to select?

Why:

I'm considering semi-permenantly mounting a couple USB drives inside my lappy's chassis. This is because I really, really hate having to plug things into my lappy, and have them poke out all over the place, when I want them to be connected most (if not all) the time.

If I can find a small port hub, I can "steal" one of the existing external ports, run the hub off that, and that would provide me with a few internal ports for whatever I need, with one of the internal ports then wired to the "stolen" external jack, to maintain usability with all 4 regular ports.

But, the tricky part... is there a way to select which thumb drive to boot off of at boot time/in the bios? This would be ideal, so I could have several for different purposes. Or is it whichever USB port is "first" from a hardware perspective? If it's the later, I'd want to determine the last boot port and use that one to set up the internal drives, to remain able to boot off external sticks.

Thoughts?

 

In the BIOS you can choose which drive to boot from.

 

Which USB thumb drive? I don't mean hard drive or USB drive, I mean between two USB drives - just to be clear.

If this is the case, I suppose the entry only appears when I've got two USB thumb drives actually plugged in at boot up?

 

It will probably boot from the first USB device on the device node tree. You should be able to determine which one that is from the device manager or, if need be, from the wiring diagram or block diagram (if you can find it, apparently, the service manual for the 570MRU hasn't been released, unlike the service manual for the 9262).

 

Alas, the service manual has been released - people here have it - but won't share. I've been searching online sites that sell them, but haven't had any luck finding a m570ru sm. It would definitely make the process simpler, but I suppose trial and error will work too.

I hadn't thought about just looking at the order displayed in the device manager, though, that's good stuff. Can probably get a hardware node number out of there, too.

So long as it does check them in a consistent order, I'll be fine. I just don't want to lose external usb boot capability. It'd be too bad that I can only be bootable off one internal thumb drive, though - it'd be an awesome way to integrate a very interesting multiboot system.