Format of SuperVGA information

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Offset	Size	Description
00h	4 BYTEs	(ret) signature ("VESA")
00h	4 BYTEs	(call) VESA 2.0 request signature ("VBE2"), required to receive version 2.0 info
04h	WORD	VESA version number (one-digit minor version -- 0102h = v1.2)
06h	DWORD	pointer to OEM name
06h	DWORD	"761295520" for ATI
0Ah	DWORD	capabilities flags (see #00078)
0Eh	DWORD	pointer to list of supported VESA and OEM video modes (list of words terminated with FFFFh)
12h	WORD	total amount of video memory in 64K blocks
VBE v1.x
14h	236 BYTEs	reserved
VBE v2.0
14h	WORD	OEM software version (BCD, high byte = major, low byte = minor)
16h	DWORD	pointer to vendor name
1Ah	DWORD	pointer to product name
1Eh	DWORD	pointer to product revision string
22h	WORD	(if capabilities bit 3 set) VBE/AF version (BCD) 0100h for v1.0P
24h	DWORD	(if capabilities bit 3 set) pointer to list of supported accelerated video modes (list of words terminated with FFFFh)
28h	216 BYTEs	reserved for VBE implementation
100h	256 BYTEs	OEM scratchpad (for OEM strings, etc.)

Note:

The list of supported video modes is stored in the reserved portion of the SuperVGA information record by some implementations, and it may thus be necessary to either copy the mode list or use a different buffer for all subsequent VESA calls.
Not all of the video modes in the list of mode numbers may be supported, e.g. if they require more memory than currently installed or are not supported by the attached monitor. Check any mode you intend to use through AX=4F01h first.
The 1.1 VESA document specifies 242 reserved bytes at the end, so the buffer should be 262 bytes to ensure that it is not overrun; for v2.0, the buffer should be 512 bytes.
The S3 specific video modes will most likely follow the FFFFh terminator at the end of the standard modes. A search must then be made to find them, FFFFh will also terminate this second list.
In some cases, only a "stub" VBE may be present, supporting only AX=4F00h; this case may be assumed if the list of supported video modes is empty (consisting of a single word of FFFFh).