Comment 186 for bug 1289977

@jojive in my case I hit f2 immediately after turning on the computer. That brought the bios menu on and it contained a "boot" section where, among other things, there was a list of devices from which to boot, where you can change the order.

I guess all that may vary depending on the hardware manufacturer. If F2 didn't work maybe I would try F10 or F12...