Quick answer: DVI and HDMI use the same TMDS signalling for video, so a passive adapter between them works for picture. HDMI adds audio, CEC, an Ethernet and audio return channel, and higher bandwidth in later versions; DVI has none of those. Converting DVI to HDMI therefore gives video only, while converting HDMI to DVI keeps the picture and drops the sound. Both directions stop at the bandwidth of the older link.
The two standards were developed by overlapping groups and share a signalling scheme, which is why the cheap passive adapters in a drawer actually work. The differences are in the extra pins and in the version ceiling, and those decide what a given adapter can and cannot do.
What the two links share
Four TMDS pairs
Both carry three data pairs and one clock pair, plus a display data channel for EDID and a hot plug detect line. That shared core is why a passive adapter needs no electronics: it routes the same signals to different contacts. Anything faster than the core, such as audio or control, needs pins that only one connector has.
Where the versions diverge
DVI stopped at 3.96 Gbit/s single link and 7.92 Gbit/s dual link. HDMI moved from 4.95 Gbit/s in 1.0 to 10.2 in 1.4, 18 in 2.0 and 48 in 2.1. A DVI source therefore limits the whole chain: an HDMI 2.1 display connected to it will run at DVI rates, which means 1080p60 or 1920×1200 at best.
Adapter compatibility
| Direction | Adapter | Video | Audio |
|---|
| DVI-D source to HDMI display | Passive | Yes | No |
| HDMI source to DVI-D display | Passive | Yes | Dropped |
| DVI-A source to HDMI display | Active converter | Yes, scaled | No |
| HDMI to VGA display | Active converter | Yes | Sometimes, via jack |
| DVI dual link, 2560×1600 | Dual link adapter | Yes | No |
Practical differences in use
Audio and control
HDMI carries up to eight PCM channels or a compressed bitstream, plus CEC for remote control and an audio return channel for TV audio. DVI carries none of these, so a DVI-connected display needs a separate audio lead and its own remote. That is the main reason DVI disappeared from consumer equipment even though it could match HDMI for picture.
EDID and hot plug
Both use EDID, but DVI ports do not always supply the 5 V that an HDMI sink expects on the hot plug line. The result is a source that decides no display is attached. An adapter with a power input, or a powered splitter in the chain, solves it; a passive adapter cannot.
Choosing the cable behind the adapter
The HDMI side should match the timing you need. A DVI source rarely exceeds 1080p60, so a High Speed cable is ample; if the source is HDMI 2.0 and the display is 4K60, the adapter must be rated for 18 Gbit/s and the cable for the same. The HDMI cable rating categories guide maps labels to bandwidth, and the DisplayPort 1.4 cable page covers the modern alternative if the source has DisplayPort instead.
Keep adapter chains short. Each passive adapter adds a connector pair and a short uncontrolled impedance, and at 1080p that is harmless while at 4K60 it is enough to cause sparkles. One adapter at the source end plus one good HDMI extension cable is the practical limit.
Practical scenarios
- Office PC with DVI out and a new HDMI monitor: a passive adapter at the PC end is enough; set 1920×1080 at 60 Hz and route audio to the monitor’s jack.
- Laptop with HDMI into an old DVI projector: the picture works, audio does not; use the laptop speakers or a small mixer into the room system.
- DVI-A output from a legacy KVM: a passive adapter gives nothing; a VGA to HDMI converter with a scaler is the correct part.
- Digital signage with a DVI player: check the display accepts the player’s exact timing, because signage players often output 1366×768 which some HDMI sinks refuse.
FAQ
Is HDMI better than DVI for picture quality?
At the same resolution and colour depth the digital data is identical. HDMI supports higher bandwidth in later versions, which matters above 1920×1200, and it carries audio. For a 1080p signal the two are indistinguishable.
Can I convert HDMI to DVI and keep the audio?
No. A passive adapter maps video pairs only. Audio must be extracted before the adapter, with an HDMI audio extractor, and sent separately to the display or the amplifier. Some active converters include an audio jack for that reason.
Why does the display show no signal with an adapter?
Often the 5 V line: a DVI port may not supply it, so the HDMI sink is never detected. Otherwise the source is set to a timing the sink does not list in its EDID. Try a lower resolution first, then a powered adapter.
