You could buy the smart strip power bar, that way if you turn off/on one component it will automatically turn off/on all of the others that are plugged into the strip. I set mine that so when the computer is turned off/on all my other stuff shuts off/on (TV, Marquee, etc.)
Also, I took the lazy route and avoided the bios stuff by simply rigging up a pushbutton on the front of my cab that physically pushes the front button on my computer, that way I can turn it on and off easily. And once the computer powers up the marquee and tv automatically come on too.