220-1101 Question 207
Single answerDisplayPortA technician is setting up a workstation with a laptop that has a Mini DisplayPort output. The user wants to connect the laptop to an older projector that only has an HDMI input. The technician first tries a passive Mini DisplayPort-to-HDMI cable, but the projector shows no signal. The laptop's documentation does not list Dual-Mode DisplayPort (DP++) support. Which of the following is the BEST solution?
- A
Replace the cable with an active Mini DisplayPort-to-HDMI adapter
- B
Use a Mini DisplayPort-to-DVI passive adapter and then a DVI-to-HDMI passive adapter
- C
Enable MST in the operating system display settings
- D
Use a USB-C-to-HDMI adapter connected to the Mini DisplayPort port
Show answer and explanation
Correct answer: A
Explanation
This question tests practical troubleshooting of DisplayPort interoperability. A key best practice is to verify whether a DisplayPort source supports Dual-Mode DisplayPort (DP++). Passive DisplayPort-to-HDMI and DisplayPort-to-DVI adapters only work when the source can send TMDS signaling for HDMI/DVI. If DP++ is not supported, the technician must use an active adapter that performs signal conversion from DisplayPort to HDMI. This is a common real-world issue when connecting newer laptops or docking solutions to older projectors and displays. DisplayPort documentation and vendor adapter guidance typically distinguish passive adapters for DP++ sources from active adapters for native DisplayPort-only outputs. Knowing that MST is unrelated to protocol conversion and that USB-C adapters are not interchangeable with Mini DisplayPort adapters reflects the applied troubleshooting expected on A+ Core 1.
- A. Correct.
Correct. A passive DisplayPort-to-HDMI cable or adapter relies on Dual-Mode DisplayPort (DP++), where the source device can output an HDMI/DVI-compatible signal over the DisplayPort connector. If the laptop does not support DP++, a passive adapter will not work. An active Mini DisplayPort-to-HDMI adapter converts the native DisplayPort signal to HDMI and is the appropriate fix in this scenario.
- B. Incorrect.
Incorrect. This still depends on passive signal adaptation and adds unnecessary conversion steps. If the Mini DisplayPort source does not support DP++, passive conversion to DVI or HDMI will fail because the source is not outputting a compatible TMDS signal. Chaining passive adapters is not a reliable solution here.
- C. Incorrect.
Incorrect. MST (Multi-Stream Transport) is used for daisy-chaining or driving multiple displays from a DisplayPort connection when supported. It does not solve signal-format incompatibility between native DisplayPort output and HDMI input on a projector.
- D. Incorrect.
Incorrect. A USB-C-to-HDMI adapter requires a USB-C port that supports video output, such as DisplayPort Alt Mode. It cannot be connected to a Mini DisplayPort port, because Mini DisplayPort and USB-C are different physical interfaces with different signaling requirements.