* Power off the monitor * Disconnect all cabling from the monitor (especially the power cord) * While disconnected, press and hold the monitor power button down for 3 seconds * Reconnect the power cord to the monitor * Power on the monitor. If the image appears for "there is no signal", good * Press the monitor OSD menu button. Does the menu now appear? If not, the monitor should be exchanged if still under the Dell warranty. Open the top announcement, "24" and smaller monitors do not get a Dell service tag number"