How to Convert VGA to HDMI or DVI to HDMI? Choose a Right Converter/Adapter Cable for Best Video Conversion!
2022/05/13 ｜By G Editor
There're almost high-resolution new monitors when you search for an external monitor, but my computer supports only VGA or DVI unfortunately. Nowadays, almost all monitors on the market have HDMI interfaces, some of them even come with USB Type-C(DP Alt) or Thunderbolt ports. For those traditional machines or computers, it is getting harder to find new and high-resolution monitors to fit with them.
Don't worry! Next, we’ll tell you how to convert the VGA/DVI video signals to HDMI port of a monitor through an adapter cable or converter.
The Evolution and Comparison of VGA, DVI and HDMI
Before getting to the point, let's quickly look at the differences between VGA, DVI, and HDMI.
1. VGA(also known as D-Sub), a video interface commonly used by early graphics cards, is used to transmit analog video signals to the screen. Its resolution and color loading are relatively poor. And it is susceptible to noise interference, which distorted the signal.
2. DVI transmits digital signal, making sure its completeness in the way of transmission. DVI ports can be sorted by ❶single link or dual link and ❷DVI-I or DVI-D( DVI-A is not mentioned here). Dual-link connector has 8 more pins in the middle than single link connector to support higher resolution, as DVI-I has 4 more pins on the left to support analog signal.
3. HDMI connector is smaller than VGA and DVI. In these three interfaces, HDMI is the only one allowing audio signal transmission. The HDMI 2.0 version can support 4K @50Hz/ 60Hz resolution. The latest HDMI 2.1 version can even support up to 4K @120Hz and [email protected]
| Connector | Signal Type | Audio Supported | Max. Resolution Supported | Best Transmission Length |
| VGA(D-Sub)
|
Analog | No | 1920x1080 | ≤15M |
| DVI-Single Link
|
DVI-I: Digital/Analog DVI-D: Digital |
No | 1920x1200 | ≤5M |
| DVI-Dual Link
|
2560x1600 | ≤5M | ||
| HDMI
|
Digital | Yes | 4K | ≤15M |
The Conversion of VGA to HDMI
We'll demonstrate the connections by GeChic T1 series touch monitors in this article. Here we go!
*All monitors of GeChic supports HDMI Full HD 1920x1080 resolution, for the other models, please refer to the connection methods in the following content.
From VGA to HDMI, the conversion progress needs to convert analog signal to digital signal. Therefore, a build-in IC chip inside the converter/adapter cable is required to get the signal conversion done! This IC chip requires power supply so please notice whether the VGA to HDMI converter has a proprietary power cable for it.
We use the converter together with its power cable and audio cable to demonstrate. If you don’t need to output audio, you don’t need to connect the audio cable.
(T1 series monitors are not equipped with built-in speakers. If you need to output audio from the monitor, you need to connect a headphone or speakers to the headphone out jack on the back of T1 monitor. )
The Conversion of DVI to HDMI
You can find two types— converter or adapter cable on the market. We suggest that you choose the adapter cable to make DVI signal convert to HDMI signal. Through JUST one cable, the transmission is easier and steadier.
We use a HDMI to DVI adapter cable supporting DVI-D dual link to demonstrate the connection. Connect the end of DVI connector to the computer and plug the HDMI connector into T1 touch monitor.
FAQ
1. The monitor displays image but not outputs audio?
● The VGA interface doesn't support audio output. VGA to HDMI converter may come with a 3.5mm audio cable for audio output from the computer. Please connect the audio cable to the adapter and audio-out jack on the PC and then audio will be transmitted to GeChic monitor through HDMI input. However, Gechic T1 and 1306 series monitors aren't equipped with built-in speakers, if you want to play audio on the monitor, you need to connect a headphone or external speakers to the audio jack on the monitor.
● DVI doesn't support audio output. When you convert DVI to HDMI, the audio can only output from the computer/ main device. Please connect a headphone or speakers to the audio-out jack on the computer.
2. Poor display performance or no signal?
① Re-plug the cables/ converter to make sure each connector is properly connected.
② (For VGA to HDMI) Please connect the power cable to VGA converter. Insufficient power supply may make the IC chip on the adapter unable to work normally, resulting in the unstable display of the monitor.
③ Restart the computer to have the graphic card detect and enable input signals.
④ Check the input source of the monitor has been set to HDMI(When several input sources are available)
*If the above steps still can’t solve the issue, please change the adapter, cables. Also, check if the connector is malfunctioning.
3. Does the resolution get worse after the video signal is converted?
For GeChic T1 monitors, with resolution 1920x1080, if the video output of VGA or DVI is 1920x1080, the image quality keeps the same based on the same resolution.
The only difference is the grayscale range. The grayscale (RGB Range) of DVI and VGA is 0~255, while HDMI is 16~235. Compared with transmission of DVI to DVI, DVI to HDMI will lose 13% of grayscale. You can set the quantization range to "Limited Range" in the graphic card control panel, and then choose "Standard 1"in the OSD menu of Gechic monitor to make apply to RGB range 16~235. This can make the HDMI monitor fit the RGB range input.
4. How long can the total length of the adapter cable be connected?
As mentioned above, the most stable transmission distance of DVI signal is within 5 meters, VGA is 15 meters, and the total length of HDMI connection should not exceed 15 meters. The longer the cable length is, the more the signal is attenuated, and it is easy to cause poor image input.