Help with ubuntu?

I ahve just bought a new 320 gig External Hard drive to stick Ubuntu on. The problem is, when I press f+12 at the startup, it dosn't find my External Hard Drive? Do you think thi shas something to do with the liinux distro or my PC?

have all of your drivers for your hd been installed?

go into your bios settings… its different on all machines, usually its the delete key. Hold it down on start up, go to boot prefrence and put the removeable hard drive as first.