model was being used. While the initial IBM PC supported only monochromatic text games, game developers nevertheless ported mainframe and other simple text games to the PC, such as Infocom with Zork. IBM introduced video display controllers such as the Color Graphics Adapter (CGA) (1981), the Enhanced Graphics Adapter (EGA) (1984) and the Video Graphics Array (VGA) (1987) that expanded the computer's ability to display color graphics, though even with the VGA, these still lagged behind those of the Amiga. The first dedicated sound cards for IBM PC compatibles were released starting in 1987, which provided digital sound conversion input and output far exceeding the computer's internal speakers, and with Creative Labs' Sound Blaster in 1989, the ability to plug in a game controller or similar device. In 2008 Sid Meier listed the IBM PC as one of the three most important innovations in the history of video games. The advancement in graphic and sound capabilities of the IBM PC compatible led to several influential games from this period. Numerous games that were already made for the earlier home computers were later ported to IBM PC compatible system to take advantage of the larger consumer base, including the Wizardry and Ultima series, with future installments released for the IBM PC. Sierra On-Line's first graphical adventure games launched with the King's Quest series. The first SimCity game by Maxis was released in 1989. The Apple Macintosh also arrived at this time. In contrast to the IBM PC, Apple maintained a more closed system on the Macintosh, creating a system based around a graphical user interface (GUI)-driven operating system. As a result, it did not have the same market share as the IBM PC compatible, but still had a respectable software library including video games, typically ports from other systems. The first major video game publishers arose during the 1980s, primarily supporting personal computer games on both IBM PC compatible games and the popular earlier systems along with some console games. Among the major publishers formed at this time included Electronic Arts, and Broderbund, while Sierra On-Line expanded its own publishing capabilities for other developers. Activision, still recovering from financial impacts of 1983 video game crash, expanded out to include other software properties for the office, rebranding itself as Mediagenic until 1990. Early online games Dial-up bulletin board systems were popular in the 1980s, and sometimes used for online gaming. The earliest