{{Short description|Graphics adapter and display standard for early IBM PCs}} {{Infobox GPU | name = Professional Graphics Controller | image = [[Image:Professional Graphics Controller by IBM.jpg|230px|PGC card]] | designfirm = [[Vermont Microsystems]] | marketed_by = [[IBM]] | codename = | created = {{Start date and age|1984|09}} | transistors = | architecture = [[Intel 8088]] | entry = | midrange = | highend =[[IBM]] 1501 PGC<br>[[Matrox]] PG-640, PG-1280 and QG-640<br>[[Dell]] NEC MVA-1024<br>[[Everex]] EPGA<br>[[Orchid Technology]] TurboPGA<br>Vermont Microsystems IM-640 and IM-1024 | enthusiast = | openglversion = | d3dversion = | predecessor = [[Color Graphics Adapter]] | successor = [[Video Graphics Array|VGA]], [[IBM 8514|8514]] }}
'''Professional Graphics Controller''' ('''PGC''', often called '''Professional Graphics Adapter''' and sometimes '''Professional Graphics Array''') is a [[graphics card]] manufactured by [[IBM]] for PCs.<ref name="TechRef">{{Cite book |url=http://www.minuszerodegrees.net/oa/OA%20-%20IBM%20Professional%20Graphics%20Controller.pdf |title=IBM Personal Computer Professional Graphics Controller Technical Reference |publisher=lBM Corporation |date=August 15, 1984}}</ref> It consists of three interconnected [[Printed circuit board|PCBs]], and contains its own processor and memory. The PGC was, at the time of its release, the most advanced graphics card for the [[IBM Personal Computer XT|IBM XT]] and aimed for tasks such as [[Computer-aided design|CAD]].<ref name="seasip1">{{cite web |last=Elliott |first=John |date=August 11, 2010 |title=Professional Graphics Controller Notes |url=http://www.seasip.info/VintagePC/pgc.html |accessdate=2014-06-19 |publisher=John Elliott's homepage}}</ref> It was designed and manufactured for IBM by [[Vermont Microsystems]], a start-up company founded by ex-IBM employees.
==Specifications== Introduced in September 1984,<ref name="IBM_AnnLtr">{{cite web |date= 10 September 1984|title=Announcement Letter Number 184-112 dated September 10, 1984: IBM 5175 PERSONAL COMPUTER PROFESSIONAL GRAPHICS DISPLAY AND PERSONAL COMPUTER PROFESSIONAL GRAPHICS |url=http://www-01.ibm.com/common/ssi/ShowDoc.wss?docURL=/common/ssi/rep_ca/2/897/ENUS184-112/index.html&lang=en&request_locale=en |accessdate=2016-08-08 |website=IBM United States}}</ref> the Professional Graphics Controller offered a maximum resolution of {{resx|640|480}} with 256 colors on an [[analog signal|analog]] [[RGB color model|RGB]] [[Video monitor|monitor]] via a [[#DE-9 video connector|DE-9]] connector, at a [[refresh rate]] of 60 hertz—a higher resolution and color depth than [[Color Graphics Adapter|CGA]] and [[Enhanced Graphics Adapter|EGA]] supported. This mode is not [[BIOS]]-supported. It was intended for the [[computer-aided design]] market and included 320 KB of display [[Random-access memory|RAM]] and an on-board [[Intel 8088]] microprocessor. The 8088 ran software routines for 2D and 3D graphics such as "draw polygon" and "fill area" from an on-board 64 KB [[Read-only memory|ROM]] so that the host [[Central processing unit|CPU]] didn't need to load and run these routines itself.<ref name="IBM_AnnLtr" /> While never widespread in consumer-class personal computers, its {{USD|2995|1984|round=-2}} list price, plus $1,295 display, compared favorably to US$50,000 dedicated CAD [[workstation]]s of the time (even when the $4,995 price of a [[IBM Personal Computer XT|PC XT]] Model 87<ref>{{Cite web |date=1983-06-07 |title=Announcement Letter Number 183-082 dated June 7, 1983: IBM PERSONAL COMPUTER AND IBM PERSONAL COMPUTER XT ENHANCED WITH ANNOUNCEMENT OF MATH CO-PROCESSOR |url=https://www.ibm.com/common/ssi/cgi-bin/ssialias?appname=skmwww&htmlfid=897/ENUS183-082&infotype=AN&mhq=IBM%20Personal%20Computer%20XT%20announcement&mhsrc=ibmsearch_a&subtype=CA |access-date=2023-04-06 |website=IBM United States |language=en-US}}</ref> was included).
==Development== The Professional Graphics Controller was developed by [[Winooski, Vermont|Winooski]]-based start-up company [[Vermont Microsystems]]. Founded by two ex-IBM employees, VMI won a competitive bid to develop IBM's next-generation graphics adapter for the [[IBM Personal Computer|IBM PC]] in 1983.<ref name=lotus>{{cite magazine | last=Freiberger | first=Paul | date=January 1987 | url=https://link.gale.com/apps/doc/A6169138/GPS?u=fcla_main&sid=bookmark-GPS&xid=a63423de | title=Building a Company in Vermont | work=Lotus | volume=3 | issue=1 | page=21 | via=Gale}}</ref> Their partnership resulted in the PGC, designed to allow the PC to run [[CAD/CAM]] software in high [[Image resolution|resolution]] and [[color depth]].<ref name=lotus /><ref name=fighting>{{cite magazine | last=Kennedy | first=Kevin | date=January 1987 | id={{ProQuest|200571402}} | title=Fighting Back from the Brink | work=Vermont Business | publisher=Lake Iroquois Publishing | volume= | issue= | page=24}}</ref> The PGC was principally designed by [[Curtis Priem]], then a recent hire of VMI who later co-founded [[Nvidia]] in 1993.<ref>{{cite web | last=John | first=Steven | date=April 13, 2025 | url=https://www.businessinsider.com/curtis-priem | title=Meet Nvidia co-founder Curtis Priem, who helped found and build the AI powerhouse | work=Business Insider | publisher=Insider Inc. | archiveurl=https://web.archive.org/web/20260326161007/https://www.businessinsider.com/curtis-priem | archivedate=March 26, 2026}}</ref> While IBM initially only wanted VMI to design the PGC while leaving manufacturing to IBM, Richards refused to agree to the bid unless IBM also allowed VMI to manufacture the cards as well. In a move described as uncharacteristic by ''[[The Wall Street Journal]]'', IBM agreed to these terms.<ref name=wsj>{{cite news | last=Gupta | first=Udayan | date=July 10, 1986 | id={{ProQuest|397989897}} | title=Playing It Safe: Technology Firms Act to Minimize the Risks of Their Ties to IBM | work=The Wall Street Journal | publisher=Dow Jones & Company | page=1}}</ref>
The PGC was discontinued in 1987 with the arrival of [[Video Graphics Array|VGA]] and [[IBM 8514|8514]].
==Software support== 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's ''[[Graphical Kernel System]]'', ''[[P-CAD]] 4.5'', ''VersaCAD'', Canyon State Systems ''CompuShow''<ref name="seasip1" /><ref>{{cite web |date= |title=CompuShow History |url=http://www.cshowplace.com/history.htm |accessdate=2016-08-08 |website=The "Cshow" Place}}</ref> and ''[[AutoCAD]] 2.5''.<ref>{{Cite news |last=Milburn |first=Ken |date=September 29, 1986 |title=Autocad ADE-3, Version 2.5 |pages=49 |work=InfoWorld |url=https://books.google.com/books?id=pzwEAAAAMBAJ&pg=PA49}}</ref>
==Output capabilities== [[File:Birds Professional Graphics Controller.png|thumb|320x320px|Simulated image as displayed using the Professional Graphics Controller {{resx|640x480}} with 256 colors resolution ]] PGC supports: * '''{{resx|640x480}} with 256 colors''' from a palette of 4,096<ref name="seasip1"/> ([[List_of_monochrome_and_RGB_color_formats#12-bit_RGB|12-bit RGB palette, or 4 bits per color component]]). * '''[[Color Graphics Adapter]] text and graphics modes'''. Text modes use a font with 8×16-pixel character cells<ref name=TechRef/> and have 400 rows of pixels.<ref name="IBM_AnnLtr" />
There are six possible color arrangements:<ref name="seasip1" />
* '''Default 256-colour palette''' - Low 4 bits intensity, high 4 bits colour; * '''16-colour palette''' - Makes the PGC behave as two 16-colour planes. If high 4 bits are 0, low 4 bits are colour; otherwise, high 4 bits are colour; * '''[[List of monochrome and RGB color formats#2-3-3 bit RGB or 4-8-8 levels RGB|2-3-3 palette]]''' (Palette 2) - Bits 6-7 red, bits 3-5 green, bits 0-2 blue; * '''[[List of monochrome and RGB color formats#3-2-3 bit RGB or 8-4-8 levels RGB|3-2-3 palette]]''' (Palette 3) - Bits 5-7 red, bits 3-4 green, bits 0-2 blue; * [[List of monochrome and RGB color formats#8-bit RGB (also known as 3-3-2 bit RGB or 8-8-4 levels RGB)|'''3-3-2 palette''']] (Palette 4) - Bits 5-7 red, bits 2-4 green; bits 0-1 blue; * '''[[Color depth#8-bit color|6x6x6 colour cube]]''' - six equally spaced shades of red, green, and blue.
==Operation== The display adapter was composed of three physical circuit boards (one with the on-board microprocessor, [[firmware]] ROMs and video output connector, one providing [[Color Graphics Adapter|CGA]] emulation, and the third mostly carrying RAM) and occupied two adjacent [[Expansion card|expansion slots]] on the XT or AT [[motherboard]] or the Expansion Unit;<ref>{{cite web |last=R. |first=Bill |title=The IBM PGA Graphics Adapter |url=http://incolor.inebraska.com/bill_r/ibm_pga_graphics_adapter.htm |url-status=dead |archiveurl=https://web.archive.org/web/20160807092417/http://incolor.inebraska.com/bill_r/ibm_pga_graphics_adapter.htm |archivedate=2016-08-07 |accessdate=2016-08-08 |website=Bill's Home Page}}</ref> the third card was located in between the two slots. The PGC could not be used in the [[IBM Personal Computer|original IBM PC]] without the 5161 Expansion Unit due to the different spacing of its slots.
In addition to its native {{resx|640x480}} mode, the PGC optionally supported the documented text and graphics modes of the [[Color Graphics Adapter]], which could be enabled using an onboard jumper. However, it was only partly [[Processor register|register]]-compatible with CGA.
==Related monitor== The PGC's matching display was the '''IBM 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 with [[VGA]], [[Macintosh]], and various other analog [[RGB color model|RGB]] video sources.<ref>{{cite web|url=http://groups.google.com/group/comp.sys.ibm.pc/msg/da3cd6fd21d0ef3f |title=Google Discussiegroepen |date= |accessdate=2014-06-19}}</ref> 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|date=November 2009}}
==DE-9 video connector== [[File:DE-9 and DE-15 video port comparison.jpg|thumb|right|Back of a PC with two video cards that output analog RGB (VGA) signals, one with a 9-pin connector on the right, and the other with a 15-pin connector left of it. Also shown are 9-pin and 25-pin serial ports on the far left, a 25-pin parallel port below them, and PS/2 keyboard and mouse ports.]] The DE-9 connector used on the IBM Professional Graphics Controller (PGC) was a 9-pin connector like the Color Graphics Adapter (CGA) and Enhanced Graphics Adapter (EGA) but was otherwise a (would later become) VGA-compatible RGB signal. Significantly, early [[NEC MultiSync]] monitors had a 9-pin male port on the back with this pinout. This was used in some early VGA and VGA-compatible hardware because the standard pre-existed VGA. It is also found in some industrial hardware from the era.
This "9-pin VGA" lacks several pins compared to full VGA, which was usually not problematic because the autodetection features supported by those pins only evolved over time, and prior to [[Windows 95]], there was no user expectation of graphics cards and displays being fully [[plug and play]]. DE-9 "VGA" connectors generally all used the same pinout, and adapters to the DE-15 standard have been made.<ref>{{cite web | url=http://pinouts.ru/VideoCables/9to15VGA_pinout.shtml | archive-url=https://web.archive.org/web/20101219164032/http://pinouts.ru/VideoCables/9to15VGA_pinout.shtml | archive-date=19 December 2010 | title=9 to 15 pin VGA cable pinout and wiring @ old.pinouts.ru }}</ref> Ultimately all VGA hardware makers switched to standard DE-15 connectors, relegating the early variant to relative obscurity.
DE-9 is the same physical size as DE-15, the latter being a high density configuration in the same "E" shell.
{| class="wikitable" |+ PGC/VGA DE-9 connector pin signals |- ! Pin ! PGC ! VGA ''de facto'' |- | 1 | Red (R) | Red (R) |- | 2 | Green (G) | Green (G) or sync-on-green (Gs){{efn|E.g. the NEC Multisync 1 supported sync-on-green.}} |- | 3 | Blue (B) | Blue (B) |- | 4 | Composite sync (S) | Horizontal (H) or composite sync (S) |- | 5 | Mode select | Vertical sync (V) |- | 6 | Red return | Red return |- | 7 | Green return | Green return |- | 8 | Blue return | Blue return |- | 9 | Sync ground | Sync ground |}
==Hardware derivatives== *[[Matrox]] PG-640, PG-1280, QG-640 (for the DEC [[MicroVAX]]),<ref name="seasip1"/> VG-640 (VME) *[[Dell]] NEC MVA-1024 card<ref>{{Cite web |last=Vlask |title=NEC MVA 1024 |url=https://www.vgamuseum.info/index.php/cpu/item/940-nec-mva-1024 |access-date=2024-12-13 |website=VGA Legacy MKIII |language=en-gb}}</ref> *[[Everex]] EPGA<ref>{{Cite web |last=Elliott |first=John |date=August 11, 2010 |title=Professional Graphics Controller Notes - Clones |url=https://www.seasip.info/VintagePC/pgc.html#clones |access-date=2024-12-13 |website=John Elliott's homepage}}</ref> *[[Orchid Technology]] TurboPGA<ref>{{Cite book |url=https://www.dosdays.co.uk/media/orchid/TurboEGA/Orchid%20TurboPGA%20Brochure.pdf |title=Orchid Turbo PGA |publisher=Orchid Technology}}</ref> *[[Vermont Microsystems]] IM-640, IM-1024<ref>{{Cite news |date=September 22, 1986 |title=Image Manager 1024 advert |pages=6 |work=InfoWorld |url=https://books.google.com/books?id=ZS8EAAAAMBAJ&pg=PA6}}</ref>
==See also== *[[List of defunct graphics chips and card companies]] *[[PC/GX]] *[[Timeline of early 3D computer graphics hardware]]
==Notes== {{Notelist}}
==References== {{Reflist}} ;Notes {{refbegin}} *Mueller, Scott (1992) ''Upgrading and Repairing PCs, Second Edition'', Que Books, {{ISBN|0-88022-856-3}} - which says 3 slots and "adapter" *[http://domino.research.ibm.com/tchjr/journalindex.nsf/0/6829ccaf443f3a6c85256bfa00685b97?OpenDocument A Professional Graphics Controller] by K. A. Duke and W. A. Wall, IBM Systems Journal {{refend}}
==External links== *[http://www.seasip.info/VintagePC/pgc.html Professional Graphics Controller: Notes - Pictures and programming information]
{{Computer display standard}} {{IBM personal computers}}
[[Category:Graphics cards]] [[Category:Display technology]] [[Category:IBM video hardware]] [[Category:Computer-related introductions in 1984]]