 | |
| Release date | 1984; 42 years ago (1984) |
|---|---|
| Architecture | Intel 8088 |
| Cards | |
| High-end | IBM 1501 PGC Matrox PG-640, PG-1280 and QG-640 Dell NEC MVA-1024 Everex EPGA Orchid Technology TurboPGA Vermont Microsystems IM-640 and IM-1024 |
| History | |
| Predecessor | Color Graphics Adapter |
| Successor | VGA,8514 |
Professional Graphics Controller (PGC, often calledProfessional Graphics Adapter and sometimesProfessional Graphics Array) is agraphics card manufactured byIBM for PCs.[1] It consists of three interconnectedPCBs, and contains its own processor and memory. The PGC was, at the time of its release, the most advanced graphics card for theIBM XT and aimed for tasks such asCAD.[2]
Introduced in 1984,[3] the Professional Graphics Controller offered a maximum resolution of 640 × 480 with 256 colors on ananalogRGBmonitor, at arefresh rate of 60 hertz—a higher resolution and color depth thanCGA andEGA supported. This mode is notBIOS-supported. It was intended for thecomputer-aided design market and included 320 KB of displayRAM and an on-boardIntel 8088 microprocessor. The 8088 ran software routines such as "draw polygon" and "fill area" from an on-board 64 KBROM so that the hostCPU didn't need to load and run these routines itself.[3] While never widespread in consumer-class personal computers, itsUS$2,995 (equivalent to $9,300 in 2025) list price, plus $1,295 display, compared favorably to US$50,000 dedicated CADworkstations of the time (even when the $4,995 price of aPC XT Model 87[4] was included). It was discontinued in 1987 with the arrival ofVGA and8514.
The board was targeted at the CAD market, therefore limited software support is to be expected. The only software systems known to support the PGC are IBM'sGraphical Kernel System,P-CAD 4.5,VersaCAD, Canyon State SystemsCompuShow[2][5] andAutoCAD 2.5.[6]
PGC supports:
There are six possible color arrangements:[2]
The display adapter was composed of three physical circuit boards (one with the on-board microprocessor,firmware ROMs and video output connector, one providingCGA emulation, and the third mostly carrying RAM) and occupied two adjacentexpansion slots on the XT or ATmotherboard or the Expansion Unit;[7] the third card was located in between the two slots. The PGC could not be used in theoriginal IBM PC without the 5161 Expansion Unit due to the different spacing of its slots.
In addition to its native640 × 480 mode, the PGC optionally supported the documented text and graphics modes of theColor Graphics Adapter, which could be enabled using an onboard jumper. However, it was only partlyregister-compatible with CGA.
The PGC's matching display was theIBM 5175, an analog RGB monitor that is unique to it and not compatible with any other video card without modification. With hardware modification, the 5175 can be used withVGA,Macintosh, and various other analogRGB video sources.[8] Some surplus 5175s in VGA-converted form were still sold by catalog retailers such as COMB (Close Out Merchant Buyers) as late as the early 1990s.[citation needed]