...and off? I have had my computer and monitor for about 4 years or so now. Its a dell deminsion 8300 with i believe an 18 inch dell flatscreen monitor. Just recently the monitor sometimes will start flashing on and off (about every second) I checked the connections and they seem fine but its weird cause if i slightly bump the screen it will stop flashing most of the time and be fine for hours. Seems like something is loose but im no pro. Could it be anything else? Also while its flashing if i push the monitor power button it does nothing at all.

Any help or suggestions would be great! Thanks