DisplayPort Alt Mode for USB Type-C Standard FAQ
DisplayPort 1.3 Standard FAQ
DisplayPort General FAQ

 

DisplayPort Alt Mode for USB Type-C Standard

Q:        What is the DisplayPort™ Alternate Mode (or Alt Mode) for USB Type-C?

A:         VESA, the Video Electronics Standards Association, has published a new Standard that enables the USB Type-C connector and cable to support the DisplayPort interface and audio/video (A/V) transport.

Q:        How does the USB Type-C Standard share its interface with DisplayPort?

A:         The USB Type-C Standard includes provision for Alternate Modes, which involves repurposing of the connector pins and cable wires for other interface types. Discovery of Alternate Mode support and enablement is performed through leveraging the use of the USB Power Delivery protocol.

Q:        What user benefits are derived from DisplayPort Alt Mode on USB Type-C?

A:         When using the DisplayPort Alternate Mode, the USB Type-C connector becomes the single system connection point for data, full performance AV interface, and power, either combined or individually. DisplayPort will enable the USB Type-C connector to support video resolutions of 5K and beyond.

Q:        Did VESA work together with the USB Promoter Group on developing DisplayPort Alt Mode on USB Type-C?

A:         VESA’s development of the DisplayPort Alt Mode for USB Type-C Standard was developed in collaboration with the USB 3.0 Promoter group.

Q:        Does DisplayPort Alt Mode over USB Type-C support the higher data rate options of the DisplayPort interface?

A:         Yes. The DisplayPort Alternate Mode supports full DisplayPort capability over a USB Type-C connector, including 5K video at 60 frames per second with 24 bits per pixel as recently enabled by DisplayPort version 1.3.

Q:        Does USB data, DisplayPort A/V data and power transmission co-exist on a single cable?

A:         Yes. The DisplayPort Alternate Mode is supported by the standard full-featured USB Type-C cable. DisplayPort, USB data, and power delivery can all co-exist on such cable.

Q:        Can a user connect a video sink or source device that has a conventional DisplayPort connector to another device that has the new Type-C connector?

A:         Yes. Existing DisplayPort devices will be able to connect to newer devices using the USB Type-C connector and supporting the DisplayPort Alternate Mode, using a new type of USB Type-C to DisplayPort converter cable. The converter cable will have the ability to be plugged in either direction, meaning the USB Type-C connector could be either on the video source or display sink device, with the DisplayPort connector at the other end. Both types of DisplayPort plugs will be supported (the standard DisplayPort and mini DisplayPort connectors), and of course the USB Type-C connector will still support reversible cable orientation.

Q:        Can a user connect a DockPort™ hub to a video source device that uses the new Type-C connector?

A:         Yes. An adaptor will be available to connect a DockPort capable source device that uses a USB Type-C connector to a DockPort Hub, which uses a tethered cable with a mini DisplayPort connector.

Q:        Like with DisplayPort sources devices today, will I still be able to support HDMI, DVI and VGA displays using an adapter, when using the DisplayPort Alt Mode over USB Type-C?

A:        Yes. The DisplayPort Alternate Mode will include the protocol conversion capability that is already a part of the DisplayPort Standard. This will enable cables that include the USB Type-C to HDMI adapter, as well as USB Type-C to DVI and VGA. Such cables will use the DisplayPort signal from the USB Type-C connector and perform the protocol conversion within the cable. To the consumer, this will simply appear to be a cable with a USB Type-C plug on one end, and an HDMI, DVI, or VGA plug on the other end. The conversion circuit will be built into the display-end plug.

Such protocol converter function can also be integrated into a hub device, where the hub is connected to the DisplayPort source using either a USB Type-C to USB Type-C cable, or USB Type-C to DisplayPort conversion cable. The hub would then include an HDMI, DVI, and/or VGA output.

Q:        Who owns and develops DisplayPort Standards?

A:         DisplayPort is a video interface standard administered by VESA, the Video Electronics Standards Association. DisplayPort is the new generation A/V interface developed by the GPU/display industry segment and currently undergoing rapid market adoption. DisplayPort enables high display performance and versatility, a high degree of system integration, and greater interoperability between various device types.

Q:        What type of products will use this standard?

A:         Because the USB Type-C connector is designed to be the next generated USB interface, it will appear on Smart Phones, Tablets, PCs, Notebooks, Docking Stations, Displays, Peripherals – Replaces all existing USB ports.

Q:        When will I be able to buy these products?

A:         Products should be available in 2015.

Q:        How will I know if the Type-C connector on my device supports DisplayPort?

A:         VESA is working with the USB-IF on port identification logos.

Q:        What happens if I plug my display into a Type-C port that does not support the DisplayPort Alt Mode?

A:         No video data will be received by the display, so there will be no image on the screen. Doing this will not harm your device.

Q:        How do I know which end of the cable to plug into my device?

A:         The USB Type-C to Type-C cable is reversible, and so is the USB Type-C to DisplayPort adapter cable. These can be plugged in either direction. The USB Type-C to HDMI, DVI, VGA, and DockPort converters need to be plugged into a video source device that has the USB Type-C connector.

Q:        I have a Mac with Thunderbolt that uses DisplayPort for video. Will there be a Thunderbolt to USB Type-C adapter to connect a DisplayPort monitor that uses a Type-C connector?

A:         A Thunderbolt connector on a Mac or PC uses the standard mini DP connector and supports DisplayPort as well as Thunderbolt. So for the Thunderbolt connector, you can use the standard mini DP to USB Type-C adapter cable to connect to the monitor.

Q:        Will products using the DisplayPort Alternate Mode be certified?

A:         Yes. VESA and the USB-IF are working on a comprehensive certification program.

DisplayPort 1.3 Standard

Q:        Does this mean DisplayPort 1.2 products are obsolete?

A:         Not at all. VESA develops and publishes standards like DisplayPort prior to their actual deployment in the field. DisplayPort 1.2a represents the latest interconnect available to consumers from manufacturers. The new DisplayPort capabilities included in DisplayPort 1.3 will now begin a process of hardware development and certification that will result in such capabilities becoming available to consumers in a range of products over the next few years.

Q:        What is the data transfer bandwidth of DisplayPort 1.3?

A:         By providing the option to support a new higher data transfer rate known as HBR3 (High Bit Rate 3), which provides a link rate of 8.1 Gbps per lane, DisplayPort 1.3 offers a 50% increase in total link rate to 32.4 Gbps when using all 4 lanes in the DisplayPort cable. Allowing for data coding overhead, this provides a total data transport capacity of 25.92 Gbps.

Q:        Will DisplayPort 1.3 enable further performance enhancements to 4K UHD displays?

A:         Yes, when including the new HBR3 link rate option, with DisplayPort 1.3 a 4K UHD display can operated at a 120Hz refresh rate using 24 bit color, or a 96Hz refresh rate using 30-bit color.

Q:        Does DisplayPort 1.3 support 8K displays?

A:         Yes, by using the new HBR3 link rate, DisplayPort 1.3 will support 8K displays with a 60Hz refresh rate at 24 bit color, however, the visibly lossy 4:2:0 pixel format must be used. 4:2:0 is normally acceptable for the playback of pre-recorded content, such as movies, which uses 4:2:0 pixel format for compression, but is not desirable for rendered graphics from computer or other graphics generating video sources.

Q:        Does DisplayPort 1.3 need to use image compression to support 8K displays?

A:         By utilizing the new higher HBR3 bit rate, DisplayPort 1.3 supports 8K x 4K displays using a 4:2:0 pixel format without the use of additional image compression. To support 4:4:4 pixel format at 8K x 4K, future versions of DisplayPort will employ a ‘visually lossless’ compression scheme.

Q:        Will DisplayPort 1.3 enable the use of a single connector for the new 5K x 3K displays?

A:         Yes, as DisplayPort 1.3 with HBR3 becomes available for production, we should see computers and displays that support 5K x 3K using a single cable.

Q:        When will I be able to buy products that use DisplayPort 1.3?

A:         Products that support new DisplayPort features defined in DisplayPort 1.3 will be available in 2015. First implementations will likely use DisplayPort Alt Mode over USB Type-C.

Q:        How will I know if my device supports new DisplayPort 1.3 features?

A:         Vendor packaging and on-line information should indicate the DisplayPort features supported for each product.

Q:        Will DisplayPort Alt Mode on the Type-C connector support DisplayPort 1.3?

A:         Yes. All of the features associated with DisplayPort 1.3 will be available for the DisplayPort Alt Mode.

Q:        Will Thunderbolt, which uses DisplayPort for video, support DisplayPort 1.3?

A:         We expect that other interconnect technologies that use DisplayPort as a video transport will adopt the DisplayPort 1.3 features.

Q:        How many 4K displays can I connect to my computer using DisplayPort 1.3?

A:         DisplayPort 1.3 with HBR3 will support two 4K UHD (3840 x 2160) displays at 60Hz refresh and 24-bit color, using the VESA video timing that is used with DisplayPort connections. However you will also need to check if the video source device will support such monitor configuration.

Q:        Does DisplayPort 1.3 enable support for the latest content protection?

A:         Yes, DisplayPort 1.3 enables support for HDCP version 2.2, and this will be a required for 4K@60 content playback. This requirement will apply to DisplayPort-to-HDMI 2.0 converters as well (including Type-C to HDMI 2.0 converters).

Q:        Can I connect a DisplayPort 1.3 device to a new television that supports HDMI 2.0?

A:         Existing DisplayPort source devices, such as PCs, already support HDMI televisions up to 1080p through the use of a DisplayPort to HDMI adapter. DisplayPort 1.3 defines new adapters that will enable DisplayPort source devices to support HDMI 2.0, enabling the support for 4K UHD with up to 60Hz refresh and up to full 24 bit color with the 4:4:4 pixel format. These adapters do not require the new HBR3 link rate, requiring only HBR2, but will depend on some of the protocols within the DisplayPort 1.3 Standard. Some DisplayPort 1.2a systems will be upgradable through firmware to support this new feature. These new adapters will also be available in DisplayPort Alt Mode over the USB Type-C connector.

Q:        Does DisplayPort 1.3 still support adapters to VGA, DVI and HDMI?

A:         Yes.

Q:        Does DisplayPort 1.3 enable support for camera RAW format data?

A:         Yes.

Q:        Is VESA’s new Adaptive Sync supported?

A:         Yes. This was previously known as “Free-Sync” from AMD.

Q:        How does DisplayPort 1.3 impact the capabilities of Multi-Stream?

A:         Using the DisplayPort Multi-Stream feature, combined with the new HBR3 link rate options, DisplayPort 1.3 can enable the following example display configurations, without the use of compression:

  • Two 4K UHD (3840 x 2160) displays
  • Up to Four 2560 x 1600 displays (see note 2 below)
  • Up to Seven 1080p or 1920 x 1200 displays (see note 2 below)
  • One 4K UHD display with up to Two 2560 x 1600 displays

Notes:

(1) The examples above assume the following:

  • HBR3 and Multi-Stream supported by both the video source and displays
  • 60Hz refresh with 24 bit color, using the 4:4:4 pixel format and VESA monitor timing

(2) The number of connected displays might be limited by video source capability. Typical personal computer support a maximum of 3 to 6 displays.

 

DisplayPort General FAQ

Q: I just purchased a monitor that only has a DisplayPort connection. How can I hook this up to my computer that only has VGA, DVI or HDMI?

A: There is not a cost effective way to do this. The adaptors that are available only work from a DP computer to a VGA, DVI or HDMI monitor and not the other way around. If you have a desktop you can purchase a graphics card with DisplayPort. Our best advice: Before you purchase a DP only monitor make sure you have DP on your computer.

Q: Where can I buy a DP 1.2 cable? Most of the cables are certified to DP 1.1a.

A: The DisplayPort version 1.2 standard was designed to utilize the Standard Display cable. We did this intentionally to avoid customer confusion. A DisplayPort cable is a DisplayPort cable; EXCEPT if it a “reduced bit rate” (or RBR) cable, which is typically a 15m cable designed for projector applications, and they only support up to 1080P; OR if it is an active cable, which will not support the new HBR2 rate introduced in the DP 1.2 standard.

So a cable that was tested to meet the DP 1.1a requirments also meets the DP 1.2 requirements.

Q: I am having trouble getting audio to my TV using a DP to HDMI adaptor. Can you help?

A: Yes. We have published a DP Audio User Guide for help on this topic.

Q: Is Thunderbolt replacing DisplayPort?

A: No. Thunderbolt technology actually leverages DisplayPort to deliver HD video to displays, helping to move media faster and simplify connections between devices. The support of DisplayPort within the Thunderbolt interface further shows the level of commitment towards DisplayPort within the PC industry. DisplayPort over Thunderbolt continues to support existing DisplayPort monitors as well as DVI, HDMI and VGA video output.

Q: What does Thunderbolt mean for DisplayPort? Are Intel and Apple dropping support for the standard?

A: Both Apple and Intel remain committed to DisplayPort. Apple continues to be one of the largest users of DisplayPort and Intel announced in December 2010 that it planned to accelerate adoption of DisplayPort. Intel was joined in that announcement by AMD, Dell, LG Display, Lenovo and Samsung Electronics LCD Business.

Likewise, industry analysts remain positive on DisplayPort:

  • Research firm In-Stat predicts a 100 percent increase in external DisplayPort device shipments from 2009 to 2014.
  • According to IDC, DisplayPort penetration will experience a compound annual growth rate (CAGR) of 106 percent between 2009 and 2014.
  • IDC estimates that DisplayPort will be on 89.5 percent of commercial desktops in 2014 and DisplayPort’s penetration in commercial notebooks will increase to 95 percent in 2014.

Q: Can a DisplayPort v1.1a Display be field-upgraded to DP v1.2?

A: DisplayPort v1.2 features must be designed into the Display. DisplayPort v1.1a Displays are compatible with DisplayPort v1.2 PCs though.

Examples:

  • Daisy chained monitors need input and output connectors
  • High resolution monitors with 4k x 2k resolution need DisplayPort v1.2
  • Monitors using USB over AUX channel communications need DisplayPort v1.2

Q: I am the owner of a new 27″ iMac, which I was planning to use as a high- resolution display for an HDMI equipped Blu-Ray player. I have purchased the DP-to-HDMI adaptor after being advised by Apple technical that it would function as an input, but having tried it, discovered that the device will only OUTPUT. My question is, why won’t the adaptor pass signal the other way, and what is the adaptor doing if it’s not powered, and it’s tiny, that it can’t do backwards?

A: DisplayPort-to-HDMI adaptors and DisplayPort-to-DVI adaptors are very simple and only operate one way. For instance, when a DP-to-HDMI adaptor is connected to a PC that supports DP++ (Dual-Mode) capability, the PC senses the presence of the adaptor and sends HDMI signals over the DisplayPort connector rather than DisplayPort signals. No signal conversion is performed by the HDMI adaptor. HDMI signals are merely passed through. The unique DisplayPort adaptor capability enables the PC to connect to a variety of displays via the DisplayPort connector including HDMI, DVI, and VGA. VGA adaptors are more complex and perform active signal conversion from DisplayPort to VGA. These adaptors also operate only one way. Unfortunately, HDMI does not support conversion to other display formats as does DisplayPort.

Q: I’d like to know if I use a DP –> HDMI adaptor to connect my computer to my TV, will I hear the sound with my TV or my computer?

A: DisplayPort does handle full HDMI signaling including sound but keep in mind that implementation of full HDMI signaling is an option the PC manufacturer must choose to enable. It is recommended that you check with the PC manufacturer prior to making a purchase and verify that the PC supports DP++ capability with HDMI. DisplayPort adaptors simply passes through the DVI or HDMI signal. We have published a DP Audio User Guide for help on this topic.

Q: When will DisplayPort support ‘daisy-chaining’ of Displays ? DisplayPort specification version?

A: DisplayPort v1.2, supports monitor daisy chaining.

Q: Can an existing DisplayPort device (deployed today) be field-upgraded to enable the future feature ‘daisy-chaining’? If so, how?

A: DisplayPort v1.1a displays are fully compatible with DisplayPort v1.2 PCs and graphics cards. A DisplayPort v1.1a display can be the last display in a DP v1.2 chain.
Here’s an example:
A PC with one DP connector is driving two monitors via daisy chaining. The 1st monitor is a DP v1.2 monitor with input and output connectors. The 2nd monitor is a DP v1.1a monitor. DP v1.2 PC—> DP v1.2 monitor with in & out connectors—->DP v.1.1a monitor.

Q: Is a DisplayPort to Mini DisplayPort cable going to be fully compatible in both directions? Most people use this adaptor to run a DisplayPort screen or projector from a Mac with Mini DisplayPort but I need to go the other way to run a Mac display with Mini DisplayPort from a DisplayPort on an AT Radeon 5770 on a PC. Am I likely to have full function or is the Apple implementation going to cause issues?

A: Standard DisplayPort-to-Mini DisplayPort adaptors and cables work both ways between sources and sinks:

  • Mini DisplayortP graphics card to standard DisplayPort monitor
  • Standard DisplayPort graphics card to Mini DisplayPort monitor

Q: What is the maximum length of DisplayPort cable that supports a resolution of 2560×1600?

A: 2560 x 1600 (WQXGA resolution) is supported over all 2-meter “DP Certified” cables. Some cables, due to their design, may be capable of supporting 2560 x 1600 resolution over lengths longer than 2 meters.

Q: Is the DisplayPort original signal only from the PC? Any other source? For example, I buy a TV with DisplayPort interface, Can only PC with DP interface connect to this TV? Any other possible DisplayPort device (Camcorder/Digital Camera, etc) could connect to my TV through DisplayPort?

A: If a source device has DisplayPort, such as a video player, and you connect it to a TV then it would send the video to the TV. Currently DisplayPort is primarily found in PCs because the standard is new and easy for the PC industry to implement, but it is not limited to PCs.

Q: The DisplayPort standard says that it supports audio as well as video. I purchased the Alienware M15X laptop and a DisplayPort-to-HDMI adaptor in order to connect it to my TV. I get the video but not the sound. Can you explain this please?

A: HDMI signaling is an optional DP++ feature that a manufacturer may or may not implement. DisplayPort adapters merely pass through the DVI or HDMI signal from the PC. It is recommended that you read the product specifications on the packaging and also contact the manufacturer prior to purchasing a product to ensure that the product supports DP++ with HDMI signaling.

Q: Why isn’t there a wire on pin 20 (POWER) on the standard external DisplayPort cables?

A: The reason power isn’t included in standard cables is because both source and sink devices are designed to provide power. Captive, attached cables often include the power wire. If it is desired, for example, that a particular source device utilize the power available from the mating sink device, then that Source device could include an attached or dedicated cable that carries the DisplayPort power signal. Same could be applied to a sink device.

Q: What is the difference between Mini DisplayPort and standard DisplayPort? Mini DisplayPort is what I am seeing on the Apple Macs. Does anyone have monitors that are powered, and have audio running over DisplayPort?

A: Mini DisplayPort connectors are now standardized by VESA and are fully compatible with standard DisplayPort connectors. Audio is an optional feature in DisplayPort v1.1a, and is now supported by several graphics cards and monitors.

Q: Looking for supply chain of PCB mount Mini Displayport PCB connectors. Are large connector suppliers such as Molex, Tyco, etc. producing these yet? I see a lot of standard DisplayPort connectors, but have found no Mini DisplayPort connectors.

A: Mini DisplayPort connectors are now standardized by VESA and are available from several manufactures. Check vesa.org for the latest connectors and cables that are DisplayPort Certified.

Q: On an HP dc7900 or any desktop with a DisplayPort connector, is it possible to in plug a DisplayPort-to-DVI adaptor cable and attach a DVI-to-VGA adaptor on top of that so that I could hook up 2 VGA monitors? (One monitor via the adaptors and one via the VGA connector?) Then later, when I get a monitor with DVI capability I can remove the DVI-to-VGA adaptor. Please let me know.

A: It’s recommended that you use a DP-to-VGA adaptor for the VGA monitor, and a DP-to-DVI adaptor for the DVI monitor. There are also DisplayPort v1.1a hubs available today that allow you to connect multiple monitors to a single DisplayPort connector.

Q: Have you heard of any reported problems hot plugging / unplugging a DisplayPort cable (monitor input failure, video card output failure, etc.)?

A: We’re not aware of any issues today with hot plugging DisplayPort.

Q: When I hook up my new 24 in Dell monitor to the computer through the DisplayPort cable it will not activate my monitor. What am I doing wrong?

A: You need to manually select the DisplayPort input in the monitor’s On Screen Display (OSD) with this model.

Q: How can I drive a DVI monitor and a HDMI flat screen TV simultaneously from a single DisplayPort provided on the PC? Can I “split” the DisplayPort output and then convert on output to DVI and the other to HDMI?

A: There are DisplayPort v1.1a hubs available today that allow multiple monitors to be driven from a single DisplayPort connector. Various output configurations are available for these hubs including DisplayPort, DVI, and HDMI.

Q: I have a Lenovo ThinkPad T500 laptop with a female DisplayPort out. My HDTV has only HDMI input, so I have a HDMI cable from the TV, connected to a DisplayPort-to-HDMI adaptor which connects to the laptop. I can get the video on the TV from the computer, but not the audio. What do I need to do? I thought HDMI and DisplayPort transmitted both audio and video signals.

A: HDMI signaling is an optional DisplayPort++ feature that a manufacturer may or may not implement. DisplayPort adapters merely pass through DVI or HDMI signal from the PC. It is recommended that you read the product specifications on the packaging and also contact the manufacturer prior to purchasing a PC or graphics card to ensure that the product supports DP++ with HDMI signaling.

Q: I am aware of the Dell 4310WX projector but am looking for other relatively high end projectors within the $1,200 to $2,000 range that have DisplayPort compatible with my Thinkpad w700.

A: A variety of DisplayPort projectors are available from various manufacturers. See this link.