Looks like your monitor is going into a test cycle. But you haven't provided much by way of description so I'm guessing.
firstly when the computer is shut down, the monitor then starts off yellow screen>blue>red> etc this continues about every second until monitor is turned off. i had been working on the computer removing spyware. its not my machine so not sure at what point this started. but it had started prior to me being called. regards leslan