Home

IBM PC Family  -  BIOS Video Modes


• The video modes are hexidecimal numbers, shown below as '00h' to '13h'.
• For IBM cards only; some third party cards 'behave' differently.
• For IBM cards only; some third party cards offered enhanced modes.
• For IBM cards only; some third party cards (notably Taxan made ones) use nonstandard sync frequencies.


References:
   1. IBM Color/Graphics Monitor Adapter  (CGA card)
   2. IBM Enhanced Graphics Adapter        (EGA card)
   3. Multi-Color Graphics Array                  (MCGA)
   4. Standard video modes
   5. Other

	= H.SYNC: positive at 18.43 kHz, V.SYNC: negative at 50 Hz
	= H.SYNC: positive at 15.7 kHz, V.SYNC: positive at 60 Hz       (A.K.A. EGA Mode 1)
	= H.SYNC: positive at 21.85 kHz, V.SYNC: negative at 60 Hz    (A.K.A. EGA Mode 2 or EGA High Resolution)
	= H.SYNC: 31.5 kHz, V.SYNC: 70 Hz
	= H.SYNC: 31.5 kHz, V.SYNC: 60 Hz

	Text / Graphics	Size	Mono / Colour / Greyscale	MDA card	MDA monitor on EGA card (see note 1)	CGA card	PCjr	CGA monitor on EGA card (see note 1)	EGA monitor on EGA card	MCGA	VGA  (standard)
00h	Text	40x25 chars	Greyscale	-	-	Yes shades:16 screen:320x200 char:8x8	Yes shades:16 screen:320x200 char:8x8	Yes shades:16 screen:320x200 char:8x8	Yes shades:16 screen:320x350 char:8x14	Yes shades:16 screen:320x400 char:8x16	Yes shades:16 screen:360x400 char:9x16
01h	Text	40x25 chars	Colour	-	-	Yes colours:16 screen:320x200 char:8x8	Yes colours:16 screen:320x200 char:8x8	Yes colours:16 screen:320x200 char:8x8	Yes colours:16 screen:320x350 char:8x14	Yes colours:16 screen:320x400 char:8x16	Yes colours:16 screen:360x400 char:9x16
02h	Text	80x25 chars	Greyscale	-	-	Yes shades:16 screen:640x200 char:8x8	Yes shades:16 screen:640x200 char:8x8	Yes shades:16 screen:640x200 char:8x8	Yes shades:16 screen:640x350 char:8x14	Yes shades:16 screen:640x400 char:8x16	Yes shades:16 screen:720x400 char:9x16
03h	Text	80x25 chars	Colour	-	-	Yes colours:16 screen:640x200 char:8x8	Yes colours:16 screen:640x200 char:8x8	Yes colours:16 screen:640x200 char:8x8	Yes colours:16 screen:640x350 char:8x14	Yes colours:16 screen:640x400 char:8x16	Yes colours:16 screen:720x400 char:9x16
04h	Graphics	320x200	Colour	-	-	Yes colours:4	Yes colours:4	Yes colours:4	Yes colours:4	Yes colours:4	Yes colours:4
05h	Graphics	320x200	Greyscale	-	-	Yes shades:4	Yes shades:4	Yes shades:4	Yes shades:4	Yes shades:4	Yes shades:4
06h	Graphics	640x200	Monochrome	-	-	Yes	Yes	Yes	Yes	Yes	Yes
07h	Text	80x25 chars	Monochrome	Yes screen:720x350 char:9x14	Yes screen:720x350 char:9x14 (see note 2)	-	-	-	-	-	-
08h	Graphics	160x200	Colour	-	-	-	Yes colours:16	-	-	-	-
09h	Graphics	320x200	Colour	-	-	-	Yes colours:16	-	-	-	-
0Ah	Graphics	640x200	Colour	-	-	-	Yes colours:4	-	-	-	-
0Bh				-	[EGA internal use]	-	-	[EGA internal use]	[EGA internal use]	-	-
0Ch				-	[EGA internal use]	-	-	[EGA internal use]	[EGA internal use]	-	-
0Dh	Graphics	320x200	Colour	-	-	-	-	Yes colours:16	Yes colours:16	-	Yes colours:16
0Eh	Graphics	640x200	Colour	-	-	-	-	Yes colours:16	Yes colours:16	-	Yes colours:16
0Fh	Graphics	640x350	Monochrome	-	Yes	-	-	-	-	-	Yes
10h	Graphics	640x350	Colour	-	-	-	-	-	Yes colours:4 for 64KB          16 for 128KB (see note 3)	-	Yes colours:16
11h	Graphics	640x480	Monochrome	-	-	-	-	-	-	Yes	Yes
12h	Graphics	640x480	Colour	-	-	-	-	-	-	-	Yes colours:16
13h	Graphics	320x200	Colour	-	-	-	-	-	-	Yes colours:256	Yes colours:256

Note 1	Changing the monitor type on an EGA card requires that switches on the EGA card be changed.
Note 2	Register and attribute behaviour is not quite the same as an MDA card. For more info, read the first page of the document here.
Note 3	4 colours if 64KB of RAM fitted to EGA video card; 16 colours if 128KB (or more) of RAM fitted.