Video Port Specifications
While some video port standards have different physical appearances, in some cases video standards are improved through changes to how devices make use of existing connectors and/or by changing how wires inside of cables are designed. Different video standards will also have various limitations with regards to display resolutions, refresh rates, and audio types that are supported.
VGA
VGA connections, also known as D-SUB connections, are one of the oldest PC video standards still included on modern displays and devices. Video information is sent to displays using analog signals with no audio channel. Generally the maximum resolution over VGA connections is 1920x1200.
DVI
DVI connections are somewhat unique in that they are capable of both digital and analog signals. There are various physical DVI connector pinouts which determine whether digital or analog signals are supported, as well as the maximum resolutions supported.
While a variant does exist for USB data to be carried over DVI alongside a video signal called DVI M1-DA, this is uncommon and not available on Plugable products. Typically DVI will only carry video signals.
| Connector | Digital/Analog | Max Resolution |
|---|---|---|
| DVI-I (Single Link) | Both | 2560x1600 @ 30Hz |
| DVI-I (Dual Link) | Both | 3840x2400 @ 30Hz |
| DVI-D (Single Link) | Digital Only | 2560x1600 @ 30Hz |
| DVI-D (Dual Link) | Digital Only | 3840x2400 @ 30Hz |
| DVI-A | Analog Only | 1920x1200 @ 60Hz |
HDMI
HDMI connections have gone through many revisions but the plug itself has remained the same.
As each specification increases the amount of digital data that can be transferred over HDMI cables, the quality of cables has become increasingly important for higher resolutions and refresh rates.
HDMI and DisplayPort also have special considerations for luminance and gamma (HDR) and chroma subsampling data beyond the typical 0-255 RGB values used in DVI and VGA.
This is a simplified breakdown of HDMI revisions. Far more details can be found on Wikipedia.
| HDMI Version | Max Resolution With 4:4:4 Chroma | HDR Support |
|---|---|---|
| 1.3 - 1.4b | 3840x2160 @ 30Hz 4:4:4 (4K @ 30Hz) | Dolby Vision* |
| 2.0 | 3840x2160 @ 60Hz 4:4:4 (4K @ 60Hz) 5120x2880 @ 30Hz 4:4:4 (5K @ 30Hz) |
Dolby Vision* |
| 2.0a | 3840x2160 @ 60Hz 4:4:4 (4K @ 60Hz) 5120x2880 @ 30Hz 4:4:4 (5K @ 30Hz) |
Static Metadata HDR10 Dolby Vision* |
| 2.0b | 3840x2160 @ 60Hz 4:4:4 (4K @ 60Hz) 5120x2880 @ 30Hz 4:4:4 (5K @ 30Hz) |
Static Metadata HDR10 HLG Dolby Vision* |
| 2.1 | 5120x2880 @ 60Hz 4:4:4 (5K @ 60Hz) 7680x4320 @ 30Hz 4:4:4 (8K @ 30Hz) |
Static Metadata HDR10 HLG Dynamic Metadata HDR10+ Dolby Vision* |
Dolby Vision is encoded directly into the HDMI stream, rather than being placed in a designated metadata stream. This generally results in display adapters not supporting Dolby Vision.
Additionally, while technically supported on HDMI 1.4, there are no consumer products featuring Dolby Vision in tandem with HDMI 1.4.
DisplayPort
Designed as a successor to DVI and VGA, DisplayPort has undergone specification changes similar to those of the HDMI standard. Revisions of this standard have gradually increased the resolution and refresh rate that can be communicated between a PC and display.
This is a simplified breakdown of DisplayPort revisions. Far more details can be found on Wikipedia.
| DisplayPort Version | Max Resolution With 4:4:4 Chroma | HDR Support |
|---|---|---|
| 1.0 - 1.1a | 3840x2160 @ 30Hz 4:4:4 (4K @ 30Hz) | |
| 1.2 - 1.2a | 3840x2160 @ 75Hz 4:4:4 (4K @ 75Hz) 5120x2880 @ 30Hz 4:4:4 (5K @ 30Hz) |
|
| 1.3 | 5120x2880 @ 60Hz 4:4:4 (5K @ 60Hz) 7680x4320 @ 30Hz 4:4:4 (8K @ 30Hz) |
|
| 1.4 - 1.4a | 5120x2880 @ 60Hz 4:4:4 (5K @ 60Hz) 7680x4320 @ 30Hz 4:4:4 (8K @ 30Hz) |
Static Metadata HDR10 HLG |
The addition of support for CTA 861.3 HDR standards in DisplayPort 1.4 allows for the possibility of conversion from DisplayPort 1.4 to HDMI 2.0a