Passive dongles use the DisplayPort connection to receive non-DP signaling from the connector and they ‘passively’ adjust the signals to be compliant with the connected monitor. Passive dongles are considered legacy connections, not DisplayPort connections, therefore they do not fulfill the DisplayPort connection requirement mentioned previously and cannot be used to enable 3 or more displays. They do, however, offer an affordable solution to adapt legacy displays to DisplayPort connections. Active dongles use true DisplayPort signaling to ‘actively’ translate and re-transmit the signals as the required outputs. Because they use the true DisplayPort signaling, they are considered a DisplayPort connection and meet the requirements to enable 3 or more displays. DisplayPort to DL-DVI dongles require an external power supply which is usually through a separate USB connection (the USB connection must meet the USB ‘high power’ specification).