Guys, I think you have your wires crossed.
WinPE is Windows Pre-Installation Enviroment.
It is a cut down Windows XP Operating system
used for diagnostics and as a recovery console.
PXE is Intels Pre-boot Execution Enviroment.
Used to boot off a server(for dumb terminals) or
to preset certain enviroment variables when the
machine is booting (not too sure of my expliantion here)
Classified...