Image processing · Future review · 4 min read
DisplayPort to HDMITM adapters generally cost about 7 dollars. But if you want to go the other way round, you will need to dive a whole lot deeper into your pockets. The reason? An HDMITM to DisplayPort conversion always requires an active instead of a passive adapter. But what exactly is going on inside these adapters, and is converting DP to HDMITM always that easy? And is there a difference between consumer and professional use? In this article, we explore the complete reasoning.
As already explained in a previous article, DisplayPort and HDMITM were created by different consortiums, with different applications in mind. HDMITM was conceived by manufacturers of displays, whereas DisplayPort comes from the IT-world.
In other words, we could say that DisplayPort comes from the video source side (AV receivers, computers, etc.), and HDMITM more from the visualization side (HDTV, projectors, etc.). Oddly enough, this means that the display ports are usually HDMITM ports. Although certainly not a general truth, it is more likely you want to connect a DisplayPort output to an HDMITM input than the other way round.
First, let’s talk about the similarities between DVI and HDMITM. Because HDMITM was created as a follow-up to DVI, the two standards were very similar at the beginning. They both use TMDS (Transition-Minimized Differential Signaling), a technology to transmit data.
Using a simple connector-to-connector type adapter cable, you could switch from DVI to HDMITM and vice versa. This applies to single link DVI, supporting resolutions up to 2048 x 1200. For resolutions above HD, however, there is High Speed HDMI, which diverts from the dual link DVI you would use. So you do need an active adapter to make the conversion.
Note however that HDMITM does support digital audio, whereas DVI is purely a video standard. So if you want to use both audio and video, you either need to use a (quite expensive) converter, or connect the audio to the display in a different way - for example via the headphone jack.
DisplayPort (and mini DisplayPort) on the other hand, is something completely different. It uses another signal type technology and even a lower cable voltage (3.3 V instead of the 5 V of HDMITM/DVI). This makes the passive DP-to-HDMITM adapter even more mysterious…
The clever technology that allows the use of a simple passive adapter, is called DisplayPort Dual-Mode (or DP++). Although this is an optional feature and not part of the actual standard, it is available on most consumer devices’ video cards. You might find the DP++ logo on the device, but because it is so widespread most modern consumer products don’t mention the logo anymore. Because ports that look identical can behave differently, the safest way to find out is to check the specifications of your graphics card, laptop or dock.
The theory of DP++ is actually quite simple: when the device detects an HDMITM adapter attached to it, the graphics card or GPU (Graphics Processing Unit) will automatically make a translation and send HDMITM TMDS signals via the video output.
The pins of the DisplayPort connector are then mapped onto the HDMITM pins, making the transition very simple. The system is completely plug and play, handles both video and audio, and does not need any driver to work. You don’t even really need a special adapter anymore, because there are DisplayPort to HDMITM cables available on the market.
There is normally no loss in quality when using such a dp to hdmi cable. Note however that this simple transition is limited by the TMDS signal the graphics card sends out, which is the same type of signal HDMITM used up to HDMITM 2.0. In practice, a passive adapter or cable handles Full HD at 60 Hz without trouble. Depending on the model, it will stop at 4K at 30 Hz or, at best, at 4K at 60 Hz. Anything beyond that, such as 4K at 120 Hz or 8K, calls for an active adapter.
Furthermore, when you want to connect multiple DVI or HDMITM monitors to a DisplayPort output, you will need an active adapter or splitter as well. Many graphics cards can’t support DP++ output to multiple monitors. Check with the customer service of the graphics card manufacturer for the type of adapter that suits your requirements the best.
Both standards have moved on quite a bit since this article was first published. HDMITM 2.1 introduced a new signaling method, Fixed Rate Link (FRL), which takes over from TMDS and lifts the bandwidth from 18 to 48 Gbps. In June 2025, the HDMI Forum went further with HDMITM 2.2, which reaches 96 Gbps and introduces the Ultra96 feature name for products and cables that support it. DisplayPort did not stand still either. DisplayPort 2.1 brought ultra-high bit rates, with certified DP80 cables carrying up to 80 Gbps, and it includes mandated support for VESA’s visually lossless Display Stream Compression (DSC).
For adapters, this has a clear consequence. DP++ hands the HDMITM side a TMDS signal, so a passive adapter cannot follow into the FRL era. To drive a modern HDMITM 2.1 display from a DisplayPort source, an active adapter has to translate between the two. Active DisplayPort 1.4 to HDMITM 2.1 adapters are on the market that reach 4K at 120 Hz or 8K at 60 Hz with HDR, using DSC.
The fine print matters, though. For the highest resolutions, the graphics card needs to support DP 1.4 and DSC, and some vendors advise keeping graphics drivers and display firmware up to date as well. The adapter’s own ratings set the limit too. Take a gaming PC with DisplayPort 1.4, a monitor that does 4K at 144 Hz over HDMITM 2.1, and an old DisplayPort 1.2 to HDMITM 1.4 adapter: you will end up with a lower resolution or refresh rate. The picture quality itself does not suffer in the adapter, but a mismatch between versions caps what you see.
Active adapters come as small dongles, but also as cables with the conversion chip built in. If you are not sure which one you need, an active adapter is the safer choice for 4K, high refresh rates, longer cable runs and multi-monitor setups.
When going the other way round, things are less straightforward. HDMITM does not support a way to force a signal translation onto the GPU. So an adapter with some computing power is always needed that does the computing at the connection. This explains the need for an active, more sophisticated adapter.
Two practical things to keep in mind. First, adapters are one-way streets: a DisplayPort to HDMITM adapter cannot simply be turned around to connect an HDMITM source to a DisplayPort screen. Second, check the maximum resolution and refresh rate on the box, because cheaper models stop at 1080p or 1440p, and some need extra power, often through a USB cable.
Does this easy conversion with DP++ mean that every screen or projector should just have an HDMITM interface? No, it does not, because it’s always better to connect devices which use the same protocol.
First of all, the voltage level-shifter circuit poses a restriction on the speed of the adapter. Although new adapters become available whenever an increase in bandwidth is introduced, you always need to buy the appropriate model.
Furthermore, this only applies to Single-link DVI connections. Because a Dual-link DVI signal needs 25 pins, it cannot be transmitted from a DisplayPort connector using a passive adapter. You always need an active adapter converter to make this translation.
Note also that DP++ is not available on DisplayPort Alternate Mode over USB-C (as is used on many current compact devices like smartphones and notebooks). So if you use USB-C you will always need an active adapter to connect to an HDMITM display. The good news is that this adapter hides in plain sight: a USB-C to HDMITM cable or dongle contains a small conversion chip, and models for 4K at 60 Hz exist. Do check that your USB-C port can output video at all, via DisplayPort Alt Mode or Thunderbolt.
Short on time? This overview sums it up.
Your situation | The adapter you need |
DisplayPort source with DP++ to one HDMITM display, up to Full HD at 60 Hz | A passive adapter or cable is fine |
The same setup, but at 4K | Passive works up to 4K at 30 Hz, and some models reach 4K at 60 Hz. For a safe 4K at 60 Hz, choose active |
4K at 120 Hz or 8K at 60 Hz on an HDMITM 2.1 display | An active DisplayPort 1.4 (or newer) to HDMITM 2.1 adapter with DSC support |
A source without DP++, or several HDMITM monitors on one graphics card | An active adapter |
USB-C (DisplayPort Alt Mode) to HDMITM | An active adapter, usually built into the USB-C to HDMITM cable or dongle |
HDMITM source to a DisplayPort screen | Always an active adapter. Check the resolution rating and the power needs |
Professional equipment | Use the native interface. If a product has only one interface, use an active converter |
The above text mostly applies to the consumer market. The professional market is quite different. Professional video equipment generally doesn’t have a GPU inside with DP++ capabilities. Our (and most other high-end devices) use different circuitry such as FPGA (Field Programmable Gate Array) and port processors to create the interfacing. As a result, they only accept the native signal of the interface.
For our video wall displays and projectors, Barco makes sure we offer the optimal interface to our customers. This is why on most of our visualization devices you will find both DisplayPort and HDMI connections. The customer then has the freedom to always connect a source device with the same native interface to our products. Only in markets where only one standard is used by default (such as digital cinema that only uses HDMI), we restrict ourselves to a single connector – which is more straightforward and more cost-effective.
