If you need power delay only to hide Windows logo, i think much simplier will be disable logo with programs like Restorator (or something like this). It's very simple with XP, a little tricky with Windows 7. I had the same problem (didn't want to see Windows logo during booting my cab), but i cleared all boot graphics.
Also, you can use hibernate instead of shutdown, and delete system picture "Restoring Windows...", and there will be no intro graphics when you power up your cab.