Sorry, but Compaq are the dummies. "Press Any Key," because it has capitalized first letters, implies that the "Any Key" is a proper noun. It sounds wierd, but I'd bet there would never have been a problem if they had written, "Press any key." Other companies did not have this problem.
I had a Compaq and never had any problem understanding that 'Press Any Key" means what it says. Face it, today most people wouldn't know a proper noun from a pogo stick.