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Information about computer Video Cards

QUICK LINKS

Video Card ABCs
Resolution information
Refresh rate information
Direct X Info
Video specifications
Video Card standards
Video memory specifications
 

VIDEO CARD ABCs

Video cards (video boards / video display boards / graphics cards / graphics adapter) is a physical hardware circuit board(s) which connects to the Motherboard. Video cards are also now being placed onto the computer motherboard to help bring the cost down on computers. When the video card is connected to a monitor it serves as the visual link between you and your computer, allowing you to view and manage your computers software data.

Video Cards must specify its video standards allowing end users to know what video card may or may not be capable of doing. With new computers you will most likely find SVGA standard video cards allowing you to run the majority of software applications as well as run at high resolutions. more.gif (610 bytes)

Generally most video cards shipped today are included with video memory. Video memory is built onto the video board and or motherboard allowing the video card to run at higher resolutions and run at more efficient speeds. more.gif (610 bytes)

Video cards are most commonly found in the PCI slots however with the release of the Pentium II came the AGP (Advanced Graphics Port) support this new type of slot was released on August 26, 1996. This new technology allows the card to run at 66 MHz, 32-bit bus.

With the increasing popularity of advanced gaming came new bread of video card refereed to as the 3D accelerators. These cards which generally not only allowed for 2D support but at the same time added new technologies such as Open GL and 3Dfx allowing game to run smoother and cleaner then ever before.


RESOLUTION INFORMATION

The following information applies to a desktop CRT monitors resolution. If you would like more information about LCD display resolutions please see our LCD page.

The following image is an example of a screen running at 640 x 480 which means 640 pixels are going horizontally by 480 pixels going vertically. When increasing the resolution the image will become smaller due to the screen displaying more pixels per inch.

res.gif (2067 bytes)

When setting the resolution higher you must have the needed Video Ram to support that resolution. If by chance you set your resolution higher then supported by your computers hardware you will need to follow the following steps to change the resolution depending upon operating system.

For help in setting the video resolution on your computer please see our trouble shooting video card section.

REFRESH RATE INFORMATION

The monitor refresh rate is measured in Hz which can also be called frame rate, horizontal scan rate, refresh rate, vertical frequency or vertical scan rate. When setting a monitors Hz, for example 75 Hz which is the Hz rate specified by VESA for any video resolution above or equal to 640x480 means that the computer is going to redraw the screen 75 times per second.

Refresh rates below 75 Hz can produce an often-imperceptible flicker that can cause eyestrain after long viewing.   While some cards can support as high as 120 Hz some times even higher it is recommended you run 85-90 Hz, rates beyond 90 Hz add an unnecessary processing burden.

DIRECT X INFO

First released in 1996 direct x is a set of APIs (Application Program Interface) developed by Microsoft to allow all programs to write instructions for hardware without knowing exactly what hardware is within the computer. Games which include Direct X will have the capability of utilizing multimedia and graphics accelerator features more efficiently. more.gif (610 bytes)

VIDEO SPECIFICATIONS

video.gif (4937 bytes)

The above picture illustrates a 15 Pin Video Port connector pin assignments as well as size dimension. Below is a chart explaining each function of a Video Port connector.

PIN FUNCTION
1 Red Video
2 Green Video
3 Blue Video
4 Monitor ID 2
5 TTL Ground
(monitor self-test)
6 Red Analog Ground
7 Green Analog Ground
8 Blue Analog Ground
9 Key (Plugged Hole)
10 Sync Ground
11 Monitor ID 0
12 Monitor ID 1
13 Horizontal Sync
14 Vertical Sync
15 Monitor ID 3

VIDEO CARD STANDARDS

The following is a listing of the most commonly found video standards in new and old computers. Within this chart under the specifications column you will find the types of resolutions this standard is capable of running at.

DISPLAY SPECIFICATIONS MANUFACTURE
MDA Monochrome only , text-only standard, text display at 80 x 25
Max of 720 x 350 resolution however each individual pixel is not accessible, because text-only.
Developed by IBM
CGA
Color Graphics Adapter
Max of 640 x 200 (Monochrome) in Graphics Mode.
Max of 160 x 200 (16 colors) in Graphics Mode.
Max of 80 x 25 resolution in Text Mode.
Developed by IBM
EGA
Enhanced Graphics Adapter
Max of 640 x 350 (16 colors, 60Hz) in Graphics Mode.
Max of 80 x 25 resolution in Text Mode.
Developed by IBM in 1984
PGA
Professional Graphics Adapter
Max of 640 x 400 Developed by IBM
VGA
Video Graphics Adapter
Max of 640 x 480 (16 colors) in Graphics Mode.
Max of 320 x 200 (256 colors) in Graphics Mode.
Max of 720 x 400 resolution in Text Mode.
Developed by IBM in 1987
XGA
Extended graphics array
Upgrade to the VGA video card.
Max of 1,024 x 768 (256 colors) in Graphics mode.
Developed by IBM in 1990.
SVGA
No real definition however
commonly referred to as
Super Video Graphics adapter.
Dependent upon the amount of Video memory see below chart for all available modes.  
SXGA
Super XGA
Max of 1400x1050 in Graphics Mode  
UXGA
Ultra XGA
Max of 1600x1200 in Graphics Mode  


 

VIDEO MEMORY SPECIFICATIONS

As the video resolution and color depth increases so do the required available resources. The following chart illustrates all of the resolutions and color depths available for PC computers and the amount of memory each of them take. 

RESOLUTION / COLOR 512K 1MB 2MB 4MB 6MB
640 x 480 @ 8-Bit 256 Colors X X X X X
640 x 480 @ 16-Bit (65,000 Colors)   X X X X
640 x 480 @ 24-Bit (16.7 Million Colors)   X X X X
800 x 600 @ 8-Bit 256 Colors X X X X X
800 x 600 @ 16-Bit (65,000 Colors)   X X X X
800 x 600 @ 24-Bit (16.7 Million Colors)     X X X
1024 x 768 @ 8-Bit 256 Colors   X X X X
1024 x 768 @ 16-Bit (65,000 Colors)     X X X
1024 x 768 @ 24-Bit (16.7 Million Colors)       X X
1152 x 1024 @ 8-Bit 256 Colors     X X X
1152 x 1024 @ 16-Bit (65,000 Colors)     X X X
1152 x 1024 @ 24-Bit (16.7 Million Colors)       X X
1280 x 1024 @ 8-Bit 256 Colors     X X X
1280 x 1024 @ 16-Bit (65,000 Colors)       X X
1280 x 1024 @ 24-Bit (16.7 Million Colors)       X X
1600 x 1200 @ 8-Bit 256 Colors     X X X
1600 x 1200 @ 16-Bit (65,000 Colors)       X X
1600 x 1200 @ 24-Bit (16.7 Million Colors)         X

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Copyright © 2002 Øyvind Haugland
Sist endret:  13 januar 2019
 

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