VGA - CompTIA A+ 220-1101 – 1.21

Summary

This video script delves into the history and technical aspects of Video Graphics Array (VGA), a once-popular analog video standard introduced in 1987. Now considered obsolete, VGA requires signal conversions that degrade quality, making it less preferred in the digital age. The script explains the 15-pin D-Sub connector and its diminishing presence in modern devices, except for some projectors and adapters. It also touches on VGA's association with lower resolutions and the use of basic graphics adapters in Windows when drivers are absent, emphasizing the importance of updating to manufacturer-specific drivers for optimal performance.

Takeaways

• 🔍 VGA, or Video Graphics Array, was released in 1987 and is now considered obsolete, used only for compatibility reasons.
• 📚 It's unlikely that the exam will cover VGA due to its age, but CompTIA still lists it as an objective, so understanding its limitations is important.
• 🔌 VGA uses an analog signal, which was suitable for the CRT monitors of the past but is less efficient with modern digital LCD screens.
• 🔄 The process of converting digital signals to analog and back to digital for display on LCD screens can degrade the signal quality, making VGA less preferred.
• 🔩 The VGA connector is a 15-pin D-Subminiature connector, recognizable by its D-shaped metal casing, and should be used as a last resort.
• 💻 Newer computers and graphics cards no longer include VGA connectors, favoring digital options, but it can still be found on projectors for legacy support.
• 🎥 Projectors often retain VGA connectors to avoid losing sales due to the lack of an old legacy connector, despite the trend towards digital.
• 🔗 Adapters with VGA connectors, such as USB to HDMI, are available, but since HDMI is digital, it is the preferable choice.
• 🖥️ Modern monitors typically do not have VGA connectors, and if they do, they should be avoided unless absolutely necessary.
• 📏 The term 'VGA' is sometimes used to refer to lower graphics resolutions, including SVGA or XGA, which are technically different but often grouped under VGA.
• 🛠️ In older Windows versions, the Standard VGA Graphics Adapter is used when no device driver is present, providing basic graphics support but performing poorly.
• 🚀 Later Windows versions use the 'Microsoft Basic Display Adapter', which offers better performance than the VGA adapter, but still not as good as a manufacturer-specific driver.

Q & A

What does VGA stand for?

VGA stands for Video Graphics Array.

When was VGA technology released?

VGA was released in 1987.

Why is VGA considered obsolete in modern technology?

VGA is considered obsolete because it uses an analog signal instead of a digital signal, which is less efficient and can reduce the quality of the display, especially with modern digital devices.

Why was VGA once a good choice for computer graphics?

VGA was once a good choice because it used an analog signal that was compatible with the CRT monitors of the time, requiring only one conversion from digital to analog for display.

What type of signal conversion is required when using VGA with an LCD monitor?

When using VGA with an LCD monitor, two signal conversions are required: one from digital to analog by the graphics card, and another from analog back to digital by the monitor.

What is the technical name for the 15 pin connector used by VGA?

The 15 pin connector used by VGA is technically known as a D-Subminiature connector, or D-Sub for short.

Why might you still find VGA connectors on projectors?

You might still find VGA connectors on projectors because projectors tend to support a wide range of connectors for compatibility, including legacy connectors like VGA, to avoid losing sales due to a lack of connection options.

Why are VGA connectors no longer included with new computers and graphics cards?

VGA connectors are no longer included with new computers and graphics cards because there are now many digital alternatives available that are more efficient and better suited for modern devices.

What is the difference between the Standard VGA Graphics Adapter and the Microsoft Basic Display Adapter in terms of performance?

The Microsoft Basic Display Adapter offers better performance than the Standard VGA Graphics Adapter, but neither provides the same level of performance as a device driver from the graphics card manufacturer.

Why should you update the device driver when you see the Standard VGA Graphics Adapter or the Microsoft Basic Display Adapter in use?

You should update the device driver to the manufacturer's version to ensure optimal performance and compatibility with your specific graphics hardware.

What does the term 'VGA' sometimes refer to in terms of graphics resolutions?

The term 'VGA' is sometimes used to refer to lower graphics resolutions, even though some of these resolutions have specific names like SVGA or XGA.

Outlines

00:00

📺 Understanding VGA and Its Limitations

This paragraph introduces Video Graphics Array (VGA), a technology released in 1987 that has become obsolete. Despite its age, VGA is still occasionally used for compatibility. The speaker explains that VGA uses an analog signal, which was once compatible with CRT monitors but is now less efficient due to the need for digital-to-analog and analog-to-digital conversions when used with modern digital devices like LCD screens. The paragraph also describes the 15-pin D-Sub connector associated with VGA and notes its rarity in new devices, except for some projectors and adapters. The speaker advises against using VGA unless absolutely necessary due to its outdated nature and the availability of superior digital alternatives.

05:01

🔄 Updating Graphics Adapters for Optimal Performance

The second paragraph discusses the importance of updating graphics adapters, particularly when a device is using the Standard VGA Graphics Adapter or the 'Microsoft Basic Display Adapter' as a fallback. These adapters provide basic graphics support but do not offer the performance of a manufacturer-specific driver. The speaker emphasizes that while the 'Microsoft Basic Display Adapter' is an improvement over the Standard VGA Graphics Adapter, it is still recommended to update to the manufacturer's device driver for better performance. The video concludes with a hopeful note for those who may still need to use VGA, acknowledging the rarity of such a scenario in modern times.

Keywords

💡VGA

VGA, short for Video Graphics Array, is a video display standard introduced by IBM in 1987. It is considered obsolete in modern technology due to the advancement of digital display standards. The video script discusses VGA's use of analog signals and its limitations in today's digital-centric devices, making it less preferred for video displays.

💡Analog Signal

An analog signal is a continuous signal that can vary over time and is used to represent information such as sound or images. In the context of the video, VGA uses an analog signal to communicate with older CRT monitors, which is less efficient compared to digital signals used in modern LCD screens.

💡Digital Signal

A digital signal is a discrete-time signal represented by a sequence of symbols, typically used in modern electronic devices for transmitting information. The script explains that modern computers and their peripherals, including monitors, use digital signals, making VGA's analog output less compatible and efficient.

💡CRT Monitor

A CRT monitor, or Cathode Ray Tube monitor, is an older type of display technology that uses an electron gun to scan lines of pixels on a phosphor screen. The script mentions CRT monitors to illustrate the historical context of VGA's design and its analog signal compatibility.

💡LCD Screen

An LCD screen, or Liquid Crystal Display, is a modern flat-panel display technology that uses liquid crystals to produce images. The video explains that LCD screens require a digital signal, which makes VGA's analog output less suitable due to the need for signal conversion.

💡Signal Conversion

Signal conversion refers to the process of changing a signal from one type to another, such as from analog to digital or vice versa. The script emphasizes the inefficiency of using VGA with LCD screens due to the need for two conversions, which can degrade signal quality.

💡15 Pin D-Sub Connector

The 15 pin D-Sub connector, also known as a D-Sub for short, is a type of video connector used with VGA. It is characterized by its D-shaped metal enclosure and is mentioned in the script as a recognizable feature of VGA technology.

💡Backward Compatibility

Backward compatibility is the ability of a system or product to work with older versions or components. The script discusses how VGA has been used for backward compatibility but is now rarely included with new devices due to advancements in technology.

💡Projectors

Projectors are devices that display images or video onto a screen using a variety of connection types. The video script notes that projectors often still support VGA connectors for legacy reasons, despite the trend towards digital connections.

💡USB Adapter

A USB adapter in the context of the video refers to a device that can convert a VGA signal to HDMI or another digital format. The script suggests that while VGA adapters may still be found, it is preferable to use digital connections like HDMI.

💡Graphics Adapter

A graphics adapter is a hardware component that processes and outputs images to a display. The script discusses the 'Standard VGA Graphics Adapter' and 'Microsoft Basic Display Adapter' as fallback options in Windows when a specific graphics driver is not available, illustrating the transition from VGA to more advanced graphics technologies.

Highlights

VGA, or Video Graphics Array, was released in 1987 and is now considered obsolete.

VGA technology may still appear for compatibility reasons but is not recommended for use due to better alternatives available.

CompTIA includes VGA in its exam objectives despite its age, prompting a brief explanation of its usage and drawbacks.

VGA operates on an analog signal, contrasting with modern digital signals used in computers and devices.

The historical context of VGA's design for CRT monitors is explained, highlighting the single conversion required from digital to analog.

Modern LCD screens require a double conversion process when using VGA, leading to potential signal quality reduction.

The VGA connector is described as a 15 pin D-Subminiature connector, recognizable for its D-shaped metal casing.

VGA connectors are no longer included with new computers and graphics cards due to the prevalence of digital options.

Projectors often still support VGA connectors for backward compatibility, despite the trend towards digital connectors.

VGA connectors can still be found on some adapters, such as those combining VGA with HDMI for digital signal preference.

New monitors typically lack VGA connectors, advising against their use unless absolutely necessary.

The term 'VGA' is sometimes used to refer to lower graphics resolutions, including SVGA or XGA, despite technical differences.

In older Windows versions, the absence of a graphics device driver results in the use of the Standard VGA Graphics Adapter for basic support.

The Standard VGA Graphics Adapter is slow and emulates VGA, intended only for basic graphics support when no other driver is available.

Later Windows versions use the 'Microsoft Basic Display Adapter', offering better performance than the VGA adapter.

Updating to the manufacturer's device driver from either basic adapter is recommended for optimal performance.

The video concludes with an understanding that VGA is rarely needed in modern technology but provides guidance for its use if necessary.

Transcripts

Let’s have a look at Video Graphics  Array, better known as VGA.  

VGA was released in 1987 and is now considered  obsolete. You will see it pop up now and again  

for compatibility reasons, but there is better  technology available, so you should never  

need to use VGA unless you have to. It is unlikely that you will get asked  

a question about VGA on the exam given how  old the technology is. CompTIA still has VGA  

listed as an exam objective, so I will spend  a little bit of time explaining where you  

may come across it and why you should avoid  using it in favor of newer technologies.  

VGA uses an analog signal and not a digital  signal. To understand why this was once a good  

thing, let’s consider an example. In this example  we have a computer with a VGA graphics card.  

Computers work digitally, thus communication  with the graphics card is digital. The  

data is stored digitally in the memory  on the video card. Back in the old days,  

CRT monitors used to display graphics from the  computer using an analog input signal. The VGA  

graphics card outputs an analog signal and thus is  the same signal type as the CRT monitor. Thus, one  

conversion from the computer to the monitor. Now, let’s consider what happens when we use  

a computer that outputs to an LCD screen which  is digital. Nowadays CRT monitors are obsolete  

and no longer made, so it would be rare to come  across one. As before, the computer communicates  

with the VGA graphics card digitally. The graphics card outputs an analog signal  

to the monitor since VGA was designed to use  analog. As before, a digital to analog conversion  

is performed by the graphics card. However, in  order to display the graphics on the LCD monitor,  

an analog to digital conversion must also be  performed. You can see, besides VGA being old  

technology, it is not preferred for video displays  nowadays as two conversions are required. One from  

digital to analog and then from analog back  to digital. Each time you perform a conversion  

like this, you risk reducing the quality of  the signal. Thus, since computers and their  

devices are all digital nowadays, you should  only use VGA if you have no other choice.  

The VGA connector is a 15 pin D-Subminiature  connector or D-Sub for short. It got its name  

because the metal around the connector  looks like a D shape. It is important to  

recognize this connector so you will  know to use it as a last resort.  

You will find that the VGA connector is no longer  included with computers and graphics cards. It was  

used frequently for backward compatibility, but  is now very rarely found on new devices. With a  

plethora of digital options available, there  is not much use for a VGA connector on new  

devices. You will, however, often still find  it on a lot of projectors. Projectors tend  

to support more connectors than any other  device. The reason I see behind that is,  

projectors cost quite a bit of money, even the low  budget ones, and the manufacturer does not want to  

lose a sale due to not having even an old legacy  connector on it. Thus, don’t be surprised if you  

see a VGA connector used on a projector. However,  you will find on many modern projectors the VGA  

connector is starting to disappear. The other place that you may still find  

VGA connectors is with adapters such as USB  adapters. In the case of this adapter, it has a  

VGA connector and a HDMI connector. Since HDMI is  digital, it is preferable to use HDMI over VGA.  

You will also find that new monitors don’t  tend to have a VGA connector on them anymore.  

If your monitor does have one, try not  to use it unless you have to. The main  

takeaway with VGA nowadays is, unless you have  old equipment that needs to use it, don’t.  

You may hear the term VGA used to refer to  lower graphics resolutions. Technically,  

some of the resolutions use different names like  SVGA or XGA, but a lot of the time you will hear  

these lower resolutions referred to as VGA. In older versions of Windows, when a graphics  

device driver is not present, the Standard VGA  Graphics Adapter will be used. This device driver,  

essentially, emulates a VGA graphics adapter  and thus is slow. It is designed to give you  

basic graphics support, so you don’t get  stuck without any graphics. When you see  

this device driver being used, you should  look at updating the device driver with one  

from the manufacturer of your graphics card. In later versions of Windows, the device driver  

changed to the “Microsoft Basic Display Adapter”.  This adapter offers better performance than the  

VGA adapter. You won’t be given a choice which  to use, Windows will automatically install one  

or the other when it can’t find a device driver  for the graphics adapter in your computer.  

When you see one of these graphics  adapters, you should update it to the  

manufacturer’s device driver. Although  this device driver is an improvement  

over the Standard VGA Graphics Adapter, it  still won’t give you the same performance  

as a device driver from your manufacturer. That concludes this video from ITFreeTraining  

on the VGA graphics adapter. I hope this video  has helped you understand VGA a bit better.  

Nowadays you probably won’t need to  use it, but if you do, best of luck.