Here's the scenario: you have an HP server and you need to rebuild it. To do this you need to pxe boot it, but its off site and you have no remote view when the OS is not up :-( Well I had to do this and not just 1 server... double :-( Luckily I came across a tool in the HP SmartStart Scripting Toolkit, called setbootorder.exe.
It lets me change the boot order from Windows (or WinPE) to any order I need. So I set it to Network first and at the end of the deployment I set it back to Hard Disk (If only it worked on IBM servers I'd be a happy man).
You just run "setbootorder pxe hd cdrom usb floppy" in any order you need and that's it, job done!
The Toolkit has a number of other tools in it, but this is the only one I have needed to use so far. Hope it helps someone out!
The Toolkit can be found at: http://www.hp.com/servers/sstoolkit