INT 10 - VIDEO - Realtek RTVGA - SET ???                                        
	AX = 5F03h
	BL = 0-3 (???)
Return: AH = 00h if successful
BUG:	in v3.C10, AX=5F03h on return due to improper stack restoration code
SeeAlso: AX=5F02h"RTVGA"