History
For last 25 years, graphics cards made unbelivible progress. First graphics card was produced in 1981 by IBM, named MDA (Monochrome Display Adapter) and it could draw only text with white or green color on black screen. Today minimum of standards for new graphics card is VGA (Video Graphics Array) which can draw 256 colors.
VGA is standard designed by IBM and which cloned every other manufactures. It presents minimum that all graphics cards should support, so their drivers could enable their functioning.
SVGA designed VESA (Video Electronics Standards Association) as fulfil of VGA standards allowing bigger resolutions and color number:
800 pixels × 600 pixels = 480,000 pixels
480,000 pixels × 8-bits = 3,840,000 bits
3,840,000 bits ÷ 8 bits per byte = 480,000 bytes = 0.5 MBs
XGA also designed IBM but it is often binded with resolution 1024x768 and support of drawing 65,536 colors, and requires 1.5 MB of video memory:
1024 pixels × 768 pixels = 786,432 pixels
786,432 pixels × 16-bits = 12,582,912 bits
12,582,912 bits ÷ 8 bits per byte = 1,572,864 bytes = 1.5 MBs
SXGA made better XGA standard and brings support for resolutions over 1280x1024 in 24-bit color (16,7 mil colors). Requires minimaly 4 MB of video mamory:
1280 pixels × 1024 pixels = 1,310,720 pixels
1,310,720 pixels × 24-bits = 31,457,280 bits
31,457,280 bits ÷ 8 bits per byte = 3,932,160 bytes = 3.9 MBs
UXGA brings support for resolution of 1600x1200, also presents improvements of XGA standard.
For improving quality of presentation isn't enough just to make resolution larger, but also color number must be larger
Za poboljšanje kvalitete prikaza nije dovoljno samo povećavati rezoluciju, već i broj boja koje se mogu prikazati na monitoru. Number of bits that color information is coded presents maximum number of colors that can be shown on monitor. From color number depends picture qualiy. Standards are:
8 - bitna boja (256 boja) - Pseudo Color
16 - bitna boja (65650 boja) - High Color
24 - bitna boja (16,7 miliona boja) - True Color
32 - bitna boja (4,3 milijarde boja) - Pure Color
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