Color Graphics Adapter - Competing Adapters

Competing Adapters

CGA had two main competitors:

• For business and word processing use, IBM launched its Monochrome Display Adapter (MDA) at the same time as CGA, which produced a higher resolution text display in 80×25 mode, rendering each character in a box of 9×14 pixels, of which 7×11 were the character itself. This produced sharper and more clearly separated characters than the CGA's 8×8 dots text character matrix allowed. Because of this, MDA was the preferred choice for business use. Also, IBM initially manufactured the MDA card as a printer port/MDA combo card. This meant that users wishing to connect printers to their original IBM PC would have to pay for the MDA card anyway (initially $335), while the CGA card (initially $300) could be left out to save money. While including the CGA card and connecting an existing TV set for use as a monitor allowed users to forgo the purchase of a monitor, this was not significantly cheaper than buying a monochrome monitor (initially $345) and leaving out the CGA card. Also, 80-column text was almost unusable on color composite displays, and the IBM model 5153 CGA color video display that was required to fully exploit the CGA card's capabilities was even more expensive. Since a great many PCs were sold to businesses, the sharp, high-resolution monochrome text was more desirable for running applications.

• In 1982, the non-IBM Hercules Graphics Card (HGC) was introduced, the first third-party video card to be made for the PC. In addition to an MDA-compatible text mode, it offered a monochrome graphics mode. With a resolution of 720×348 pixels, it had a higher resolution than that produced by CGA. The Hercules' combination of sharp monochrome text and graphics capabilities made it ideal for running software such as Lotus 123 that supported business graphics. Some games also had Hercules support, and most others could be made to work with HGC via SimCGA, a TSR which would reformat the CGA graphics memory to HGC format in the background.

Other alternatives:

• Important to the gaming community, the IBM PCjr (1984) and the compatible Tandy 1000 (1985) featured onboard "extended CGA" video hardware that extended video RAM beyond 16 kB, thus allowing 16 colors at 320×200 resolution and four colors at 640×200 resolution (later Tandys also had a 640×200 mode with 16 colors). Similar but less widely used was the Plantronics Colorplus.

• In 1984, IBM also introduced the Professional Graphics Controller, a very sophisticated—for its time—high-end graphics solution intended for e.g. CAD applications. It was mostly backwards compatible with CGA. The PGC did not see widespread adoption due to its $4,000 price tag, and was discontinued in 1987.

• Another extension in some CGA-compatible chipsets (including those in the Olivetti M24, AT&T 6300, the DEC VAXmate, and some Compaq and Toshiba portables) is a doubled vertical resolution. This gives a higher quality 8×16 text display and an additional 640×400 graphics mode.

The CGA card was succeeded in the consumer space by IBM's Enhanced Graphics Adapter (EGA) card, which supports most of CGA's modes and adds an additional resolution (640×350) as well as a software-selectable palette of 16 colors out of 64 in both text and graphics modes. Along with this move, the price of the older CGA card was lowered considerably; it became an attractive low-cost option and was soon adopted by the new PC cloning companies as well. Entry-level non-AT PCs with CGA graphics sold very well during the next few years, and consequently there were many games released for such systems, despite CGA's limitations. CGA's popularity started to wane after VGA became IBM's high-level standard and EGA the entry-level standard in 1987. However, most software made up to 1990 supported it.