I have Windows 8 Preview on an USB Flash Drive. I can boot from it and I come to an install screen. Is it possible to run Windows 8 from a USB Drive and not install it to the local HD (the one with Windows 7)? If so, how?
Like the guy says in the link i provided below:
The Full windows 8 installation to USB pen drive would eat around 12GB of space plus your own software applications. Other than that it would need temp and swap storage. You can live with 16gb pen drive but soon you’ll be choked to death.
Rest of the instructions can be read here, given you have a sufficiently sized pen drive
No. There is no such thing as a "live" windows 8 boot disk (or USB). In order to use the OS, you must first install it.