Hi Sandro, There are a good number of things that can be going wrong here so i have a few questions. Is the sleep LED pulsing, flashing, or solid? Flashing means reseat your ram, pulsing or solid will point to a deeper issue with the MLB. Hold a flashlight up to the LCD, is there any video at all? Is there video on an external Monitor? Check the video connection on the MLB, the [ shaped plug can be brittle. watch for the L corner of the connector breaking off causing a poor connection.