I have a Lacie external hard drive which I've used with my Compaq 1015v and XP home. This week I bought an HP G7000 latop for my wife and replaced Visa with XP though the process is ongoing. But the new laptop won't recognise the Lacie.
If the hardware is connected at startup, yes. BIOS sees and configures all hardware and passes that information to the OS. eg.. if there is even a USB thumbdrive connected it should be reported by BIOS. For hardware already connected at startup, if it is not seen [and configured] by BIOS, then it aint there, as far as the OS is concerned... [UPnP equipment connected after startup excepted, of course].
And there is not much you can do about it, either, except suspect connections and cables, plug to the rear USB ports... Your BIOS Detect UPnP devices setting is enabled, of course?