bootable USB hard drive

can anyone advise. I want to put an operating system: XP or Vista

onto a USB hard drive.How do I do this and make the drive bootable

My bios allows booting from a USB thumb drive

 

It can be done as you know, try googling it for further info if no response's here.

Think tech republic web site had info on this or an article with links to further info.

One would guess? Disable boot from Hard drives to start with and the USB drive has to be made bootable for windows to be installed on it and run.

Instead of the default C:\ windows install use the usb's drive letter as the target to install windows, if your not sure verify by size capacity or name also your p.c's drivers for the monitor video audio lan etc will need to be added to that drive.. Once done

Set boot from usb devices to enabled in Bios, you may choose to leave disabled the Hard drive boot option - so only the usb windows loads by default? or you might just alter the option and get the choice of the two operating systems at startup - choice to select / load one of the two versions of windows.

Stand back and hope all goes well,

G luck