Question Analouge or digial monitor

[PaulDesmond]

I find this odd. I have always used a 15 pin d connector which has been standered cabling to a monitor. I wanted to have a dual monitor system. Motherboard: ASRock H610-M-HVS/M.2.

I have been told that i have an analouge output and a digital output. The digital is HDMI. However I have a laptop with a HDMI output. I can conect it to a TV to watch you tube stuff. I also have a cable that converts the HDMI output of my laptop to a VGA. allowing me to connect directly to my monitor. So how can HDMI be digital and VGA be analouge?

My knowledge of analouge is a sign wave mains or the audio that I can see on a sound recorder. Digital is Computer square wave.

Can anyone unscrambple this for me. Looks like I could have 2 VGA monitors and use this converter cable.

 

[SkyNetRising]

I also have a cable that converts the HDMI output of my laptop to a VGA.

Can you show a photo of the cable?
(upload to imgur.com and post link)

So how can HDMI be digital and VGA be analogue?

It just is.
To convert digital HDMI signal to analogue VGA signal, active signal conversion is required.

Looks like I could have 2 VGA monitors and use this converter cable.

Are all your monitors with VGA input only?
Any half recent monitor will also have HDMI and/or DisplayPort inputs.

 

[PaulDesmond]

I don't have another VGA monitor but I could get the same make and model that would sit side by side. Getting another difrent model would look odd. Here is a link to the cable.

https://www.amazon.co.uk/gp/product/B078Y97QDY/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1

You said "To convert digital HDMI signal to analogue VGA signal, active signal conversion is required." BUT this is an ordinary cable no converting here."

 

[Eximo]

That is an 'active' adapter. It is converting HDMI data to RGB voltage signals. These have become quite inexpensive over the last ten years and are efficient enough to run off an HDMI port's power. But it is considered a passive adapter for another reason.

What is commonly called an active adapter these days is an adapter that produces its own clock pulse, which allows it to drive another monitor. (So if your GPU supports two monitors, but has three ports, a true active adapter would allow you to run three) Or 3 to 4, etc.

The term passive refers to the GPUs clock pulse being sent along a wire with no modifications.

 

[PaulDesmond]

So what you are saying it just clamps the voltae from a 5 volt digital to a lower voltage. I asumed by analouge is a sign wave but you are saying it would be digital but a diffrent voltage.

VGA signals are .7 Volt.

I thought true digital would be DVI, but my motherboard does not have that even though it is a mondern motherboard. Although the use of the word active here to me means electronics (Transistors, diodes, resistors).

 

[Eximo]

So what you are saying it just clamps the voltae from a 5 volt digital to a lower voltage. I asumed by analouge is a sign wave but you are saying it would be digital but a diffrent voltage.

VGA signals are .7 Volt.

I thought true digital would be DVI, but my motherboard does not have that even though it is a mondern motherboard.

I'm not sure how you arrived at that conclusion from what I wrote. Maybe the clock pulse is confusing. That signal is what drives the frequency of the display (not the refresh rate, but actual frequency, you may have seen it on older monitors in kHz). There is a limit on how many signals a GPU can produce (each monitor, even if they are the same monitor, needs a separate signal).

The VGA signal is analog. There are R, G, and B voltages for color information and varying voltage is what carries the 'data'. These would be waves when looked at over time. With CRTs that signal was directly fed into further analog circuitry to control which sub pixels to hit with the electron gun. On an LCD screen it is basically converted back into digital form at the monitor in the reverse operation of what that adapter you have does. Then it becomes analog for driving each sub pixel, in circuits called, well, drivers. Digital signals like DVI, HDMI, and Display Port get to skip this conversion step, but the data packets still have to be processed.

Why CRTs are well known for their response times and lack of input lag.

I'm trying to keep it simple without writing a paper on how it works in detail. There are better resources out there for that.

 

[kanewolf]

So what you are saying it just clamps the voltae from a 5 volt digital to a lower voltage. I asumed by analouge is a sign wave but you are saying it would be digital but a diffrent voltage.

VGA signals are .7 Volt.

I thought true digital would be DVI, but my motherboard does not have that even though it is a mondern motherboard. Although the use of the word active here to me means electronics (Transistors, diodes, resistors).

Analog video Think of audio on an oscilloscope. That is analog. It was the standard for MANY years. BUT it is susceptible to losing high frequency data and therefore losing resolution. Think about listening to headphones through a set of ear muffs. You lose fidelity. A CRT is an analog monitor, a flat panel is digital internally. So a conversion from the analog video input to the digital commands for the flat panel has to happen.
Digital video is a stream of digital data that basically says "pixel 1 = color red, brightness 12, pixel 2 = color red brightness 10, ...." Every pixel in the screen is described. And that repeats over and over. There is no fidelity loss. There is no conversion required for a digital input to a flat panel monitor.

 

[PaulDesmond]

I was an engineer designing CCTV cameras and equiptment. I have used oscilloscope and worked on valve based TV with the electon cathode guns.

The reason for all of this though is, I bought a PC nearly a year ago from a local shop. I have had nothing but trouble with it. when I am on the internet I get the MS blue screen saying it has to recover with a percentage going up. I think I need a new motherboard.
Question should I go for a VGA / DVI motherboard or similiar to this VGA / HDMI? I am hapy to buy a diffrent model of monitor is it is best. Maybe 2 of them with a choice of VGA / DVI.

 

[kanewolf]

I was an engineer designing CCTV cameras and equiptment. I have used oscilloscope and worked on valve based TV with the electon cathode guns.

That was ALL analog. CRTs are analog devices. Flat panel monitors are not.

 

[PaulDesmond]

Okay thanks.

 

[kanewolf]

I was an engineer designing CCTV cameras and equiptment. I have used oscilloscope and worked on valve based TV with the electon cathode guns.

The reason for all of this though is, I bought a PC nearly a year ago from a local shop. I have had nothing but trouble with it. when I am on the internet I get the MS blue screen saying it has to recover with a percentage going up. I think I need a new motherboard.
Question should I go for a VGA / DVI motherboard or similiar to this VGA / HDMI? I am hapy to buy a diffrent model of monitor is it is best. Maybe 2 of them with a choice of VGA / DVI.

Unless you have a CRT montior there is no reason to get a motherboard with VGA. If you have a flatpanel monitor that is so old that it only has VGA, it should be replaced when you buy a motherboard, IMO.

 

[SkyNetRising]

So what you are saying it just clamps the voltae from a 5 volt digital to a lower voltage.

There is active signal conversion circuit inside the adapter.

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