esta pàgina en Español
MDA, CGA, Hercules, EGA, VGA
Certainly, a XT supports any kind of cards only ISA type.
Let's begin with the oldest and the worst:
MDA (Monochrome Display Adaptor)
MDA is only text, that means that you only could show text
characters on the screen, not images. 80 columns and 25 rows. With this
video mode, it's not possible to play games, almost, because could play
games like tetris, chess , othelo, mastermind or pacman all in text
CGA (Color Graphics Adaptor)
1981 This is the first true "graphics mode", you could do the
same as on MDA, but furthermore have more graphics modes where you
could draw lines, circles, etc. It resolution is 320x200 (320 pixels
per horizontal line and 200 per vertical) with 4 colours to choose in a
palette of 16, and another in 640x200 black and white.
1982 although it may seem worst than CGA since it have only 2
colours its 720x348 gives us a great screen resolution then, if you
have to draw lines with some drawing software will look fine. It's
important to tell that games that were ready for Hercules looks very
EGA (Enhanced Graphics Adaptor)
In 1984 an important advance was 640x350 with 16 simultaneous
colours on screen within a palette of 65.
MCGA (Multi Color Graphics Array)
Appeared in 1987 originally incorporated in the main board on the
new IBM computers PS/2-25 and Ps/2-30, allows 320x200 but with only 256
VGA (Video Graphics Array)
In 1987 a new card type appeared on the market, ISA, it changed
radically the used resolution and the colour quantity.