XGA-2 Display Adapter/A

Extended Graphics Array-2

@8FDA.ADF IBM XGA-2 Display Adapter/A
C8FDA.ADF Init file for @8FDA.ADF

192-228 IBM PS/2 XGA-2 Display Adapter/A
194-255 Multimedia Products - MXGA Display Device Driver (by Software 2000)
July 1995 Enhanced 16-Bit Direct Color for Natural Images

XGA/XGA-2 Option v2.2 Updated XGAANI and XGAPNI.DGS
Dosdpmv.exe APM disk for DOS 5.02+ and Windows 3.1.

XGA206 Windows 95/98 XGA-2 Display Driver by Unal Z
XGA208 Windows 95/98 XGA-2 Display Driver by Unal Z

XGA2_NT4 Windows NT4 XGA-2 Display Driver w/ 16-bit color support [New!]
   Uses Unal Z's mini port driver and framebuff.dll modified by Ryan Alswede.

A.072 OS2 Warp 3/4, XGA/2, Rev 9.29, 1-14-98 (XGA2 640x480/800x600 64k)
   "Seems to have added a lot more DMQS monitor files too. All dated 10-9-97"
   Thanks to Dennis Smith for this find...

xgademo.zip XGA Demonstration v1.2 (easy install version by "Retro Erik")
   (created by Mike O'Hara of Analyst International Corporation, 1992)

41G3324 PS2 Hardware Maint Library Suppl XGA-2 Display Adapter Sep92

XGA-2 utilities by Unal Z
IBM XGA Files includes XGA212.exe (DMQS and WfW3.11)

XGA-2 Setup under DOS and Windows (by Peter Wendt)
   Resolutions and modes: Table 1 Table 2 Table 3

XGA Common Information

XGA-2 Display Adapter/A
Adapter ROM
Pumping Up the XGA-2?
Video Configuration Under Setup
Slots XGA-2 Can Use in Model 90
Installing XGA-2 On Model 95
Blank Screen Under W95 MS-DOS Mode
XGA2 Error Codes
ADF Sections

XGA-2 Display Adapter/A FRU P/N 87F4774, FCC ID ANO87F4773 [P] [P] | [P] [P] | [P]

J1 Solder pads for 2-pin header
J2 HDD15 video connector
L12 Toroid
U1 39G3309 Video BIOS
U2 02G1397 XGA-2 controller
U6 33G0329 or 89G2928 RAMDAC
U7 32Kx8 SRAM
U8,11,14,15,18,19,32,33 256Kx4 DRAM
Y1 4.000 MHz xtal

J1 Solder pads for a 2-pin jumper. What could this jumper affect? Tell Us!
U1 Video BIOS - Dated 05/94 on the blue RAMDAC version.
U7 HM62256BLFP-10T, CXK58257AM-10L, or compatible 32Kx8 SRAM (sprite/attribute buffer)
U8,11,14,15,18,19,32,33 MSM514262-80Z, TC524256BZ-10, or compatible 256Kx4 multiport DRAM (µPD42274V-10 should work too)

No factory reworks were documented on the XGA-2 adapters (except for THIS bodge wire to jump a broken trace on Louis' XGA-2 pulled from a 9577).

Adapter ROM

1x 27C256-20 32Kx8 CMOS EPROM, PLCC-32 (U27)
(TMS27PC256-20FML or compatible)

39G3310 XGA-2 BIOS ver 3.00 28-08-92



There are three different RAMDAC types:

  • early - CQFP with heatsink, P/N unknown (possibly same as "mid")
  • mid - CQFP with ceramic IHS (integrated heat spreader), P/N 33G0329
  • late - blue ceramic CQFP with exposed die (no IHS), P/N 89G2928


The XGA-2 Display Adapter/A features an 8-bit digital-to-analog converters (DACs), versus the 6-bit DACs used by XGA Display Adapter. With 8-bit DACs, the XGA-2 Display Adapter/A now supports a palette of 16.7 million possible color combinations of which 256 can be displayed at any one time. (the XGA Display Adapter allows 256 of a possible 262,144 colors.) Similarly, the XGA-2 Display Adapter/A provides 256 possible shades of grey, compared with XGA Display Adapter's 64 shades.

Version Capabilities

>If only the RAMDAC would actually run at its full spec that would be possible. Unfortunately, at least with the XGA-2 in my 'E' (9533), I am forced to run at 1024x768@70Hz (no 75Hz). 1024x768@70 is a 75MHz dot clock, whereas 1024x768@75 is an 85MHz dot clock.

Peter Wendt suggests:
   I've seen and described that effect earlier (*much* earlier) with a XGA-2 using the "heatsinked" RAMDAC... but apparently my PS/2e ran quite nice on the Eizo F35 at 1024 x 768 @ 75 Hz. Going above that will cause "speckled" icons and litter the desktop when moving objects or open / close windows.
   It also seems as if the later "white board" RAMDAC and the last "IBM blue glass" types were an improvement over the earlier versions. Same effect can be seen on Mod. 9556 / 9557: the early RAMDAC has a round "heatsink tower" glued atop - the later ones and all 486SLC3 haven't. The later ones run much more stable.
   Currently I have a "blue RAMDAC" XGA-2 in my turbo-95A. Run OS/2 Warp at 1024 x 768 / 256 colors and 76 Hz. No negative side-effects.

Pumping Up XGA-2?

From Helmut P. Einfalt:
   From what I see it *is* the regular XGA-2 card. The memory modules are Toshiba TC524256 (IC VRAM 524256 80 ns 256K*4). There exist some modules with 256k (reportedly even 512k, and maybe meanwhile some 1024k ones too) that are pin-compatible to the ones on the XGA-2, but I doubt that the card BIOS will be able to handle them. The soldering job would be bad but feasible -- physically it *might* be possible to boost the card to 2-4 MB (or even beyond), but it would require a couple of experts to read out and patch the card BIOS, and even then we'd still not have any drivers...
   Last weekend when I was at Peter's place he told me that at one point IBM obviously had thought of building the 4MB variety, but they seem to have dropped the whole thing long before the first card was up and running...
   But if anyone wants to have a go at the swapping the memory -- let me know! I'm willing to test them...

Blank Screen Under W95 in MS-DOS Mode (from Peter)

A very common mishap is that: you click the "Start" bottom / left and select "End", then select "Start MS-DOS" from Win95. Next you sit in front of a machine with a totally blanked screen.
Is the machine dead ? No - it isn't. Toggling NumLock alters the state of the NumLock LED, so the machine is still working. But the screen shows no prompt. Reboot works too.

To resolve this you might blindly type mode co80 which returns a screen with the DOS-prompt.

Now - agreed - this is only a very unsatisfying solution. You can do this automatically. Create a DOSSTART.BAT in the C:/WINDOWS directory. It contains only one line:

mode co80

This file is started any time you leave Win95 to MS-DOS - all command lines in this DOSSTART.BAT are executed when starting up the DOS. This is also the place to put keyboard-drivers to. Or probably a scanner-driver or GUEST.EXE for an IOMEGA ZIP-drive... everything you would normally start within an AUTOEXEC.BAT when you have a DOS-only machine.
However: "Real Mode" device drivers like for a CD-ROM or scanner-drivers that needs to be placed in the CONFIG.SYS cannot be put here. They will have to be installed in the CONFIG.SYS too.
But careful: a too old driver may crash Win95 or force it to run in 16-bit compatibility mode.

XGA-2 with 64K under Win95

Check out Unal Z's XGA206 and XGA208 for real XGA-2 support.

Installing the XGA-2 on the 8595

For Type 4 complexes, you have the most recent ADFs for the XGA-2 already. For older 90/95s, 55/56/57/70/80 systems you need the current XGA / XGA-2 option disk from IBM ftp and *boot* the machine with it prior to install the card. Run "Update a Model 90/95 system partition" to make sure you have the latest ADF, DGS files on the partition.
   Then install the XGA-2 physically. If you have an 8590 or 9590, all of the connectors WILL NOT fit into the slot. You have a choice of Slot 2 or Slot 4. For more details, go HERE. For the 8595 / 9595 systems, Slot #5 is the one you should use.

Next recommended step: If you are running DOS / Win 3.x or Win95 get the DOS / Win 3.x drivers Ver2.12. Run the Install from DOS and install the DMQS monitor profiles first. This avoids some error messages later on. Trust me. I'm not worried about DOS drivers, but if you are, install the DOS drivers before you leave the Install program.
Note: Do NOT load the DOS Adapter Interface device driver if you are using Windows. The DOS Adapter Interface drivers are not supported in OS/2 to run XGA resolution in a DOS full-screen, or DOS-window.

Reboot after installing DMQS.

Now for an existing Win3.1x installation, go to the Windows directory (eg- cd\windows) and run setup. Choose the video entry, go to Other, and type in the path a:\winv31 and hit enter (though a soft press works as well). You may need some of your Windows install disks. Be prepared!
   After going into Windows, go to Main>Control Panel>XGA Setup. Choose the monitor profile that comes the closest to fitting your monitor. Display shows the Display attached. Advanced shows the resolution and color depth of the display.

You can find a profile to monitor matrix HERE.

In Win95 you can force the display to use 75Hz refresh at 640 x 480 modes with using the VESA-driver XVGARATE 75 NOWARN in the AUTOEXEC.BAT - usually the XGA-2 comes out in 60Hz in that mode.
   Unlike to the XGA-1 the XGA-2 is capable to identify the attached display and set its defaults to corresponding values. For a "better than XGA" monitor select the "14 Inch VESA" with 75Hz refresh in all modes - did that for my EIZO.
   If you run OS/2 you will have to use "Change Installation" again and select XGA-2 as primary video. After installation of the drivers you will find a second page in the displays properties folder (right arrow at the bottom of the page), where you can select monitor types, resolutions and refresh rates.
   Very friendly greetings from Peter in Germany

XVGARATE rate nowarn

This utility should be used if an XGA-2 subsystem is being used as the primary VGA source in a system and a Multi-Scan type of display is attached.

Most Multi-Scan type of displays respond as an IBM 8514 display when interrogated by the XGA-2 subsystem Power-On Self Test (POST) program. As a result the VGA video will be displayed at the '60Hz' refresh rates shown below (the normal VGA rate for IBM 85xx displays).

However, if the attached display can accept one of the two alternative faster video rates, this utility may be used to override the default rate. WARNING: If this override is used in an AUTOEXEC.BAT or CONFIG.SYS, then care must be taken to ensure that the parameters specified are suitable for the attached display. Selecting the wrong video rate may result in VGA video not being displayed correctly, or even (in some cases) damage to the display over time.

If the display cannot support a chosen rate, the system must be rebooted.

Rate Resolution Frame Rate Line Rate PEL Rate
rate =60 640 x 480 60 Hz 31.6 KHz 25.175 MHz
720 x 350 70 Hz 31.6 KHz 28.322 MHz
720 x 400 70 Hz 31.6 KHz 28.322 MHz
rate =72 640 x 480 72 Hz 37.8 KHz 30.250 MHz
720 x 350 84 Hz 37.8 KHz 34.000 MHz
720 x 400 84 Hz 37.8 KHz 34.000 MHz
rate =75 640 x 480 75 Hz 39.4 KHz 31.500 MHz
720 x 350 88 Hz 39.4 KHz 35.500 MHz
720 x 400 88 Hz 39.4 KHz 35.500 MHz
nowarn = NOWARN prevents the Y/N WARNING before execution.

Video Configuration Under Setup

Video I/O Address
   This determines where in the I/O address space the video registers exist. Because you can install multiple XGA-2 controllers, the computer assigns a unique I/O address and instance number to each video controller.

Video ROM Address Space
   This determines the area of adapter ROM address space used by the video coprocessor. The video coprocessor is used when the XGA video is in the extended graphics mode. The coprocessor is not used when the XGA video is in the VGA mode.
   This area of memory (C0000 to DFFFF) is normally used for read-only memory (ROM) on adapters and is commonly used by memory managers for expanded memory or high-RAM support. A conflict might occur if both the memory manager and the video coprocessor are using the same area of memory.

Video Memory
   Many applications use the 1MB of VRAM to display high resolution, multicolor images. The video function provided by most programs work within 64K blocks, which are paged or swapped in and out of the 1MB VRAM workspace. Other programs, such as OS/2 multimedia extensions, require direct access to the entire 1MB of VRAM to operate. (OS/2 ver 2).
   The 1MB VRAM aperture is normally enabled, but will be disabled if there isn't enough memory address space available for both system memory and the 1MB VRAM aperture. For example, with 16MB of system memory installed, the video aperture and system memory contend for control of the highest 2MB of memory address space. Auto-config solves this by disabling the video aperture and gives control of the upper 1MB to the system memory.

What about the 1MB Aperture in Setup?
   The video-aperture can only set on systems with less than 16MB. It was originally planned to enhance the video-performance on smaller systems by addressing the video memory in a range below 16MB. Useless on 486-machines and with more than 16Megs of RAM. (Editor's Note: Set to DISABLED)

XGA-2 in 8590 / 9590

Problem: "The card does not fit any of the slots in my 8590. Oh well, better luck next time."

Nope. The correct statement should have been "It does not fit *with all parts* of the connector in the slot" - and this is totally correct.
   Explanation: the XGA2 offers a BVE base video extension for those machines that *do not have* a planar video system (like Mod. 77 Bermuda, Server 85 and all 95).
   The Mod. 90 has no BVE-slot - only one AVE (auxiliary video extension) which is intended for 8514A-style cards that are controlled over the Base Video and / or capable to use the Base Video for Low-Res / Text modes and / or use a video-grabber on VGA.
   So consequently the BVE-part on the XGA2 stays free when inserted in any Mod. 90 slot - except Slot 3 that has AVE intended for 8514-cards to which it does not physically fit (different position of rear part / different keying). (Model 95 BVE Slot is Slot # 5)

ADF Sections AdapterId 8FDA "XGA-2 Display Adapter/A"

If (I_100ns_Stream_Data eq 1)

Begin Device 03h 02h 01h NoDMA

Video I/O Address
    I/O (Input/Output) address range for the display ontroller registers. This field also affects the location of the video coprocessor registers. Each adapter you install must have a unique address range. Normally, the address range does not need to be changed. You must fix conflicts before you use the adapter.
        <"Instance 6: 2160h - 216Fh">, 1: 2110h - 211Fh, 2: 2120h - 212Fh, 3: 2130h - 213Fh, 4: 2140h - 214Fh, 5: 2150h - 215Fh, 7: 2170h - 217Fh, 0: 2100h - 210Fh"

1 MB VRAM Aperture Base Address (set to DISABLED)
   1 MB aperture from the PC into the video memory. If the aperture has been disabled, it is because there wasn't enough available memory address space for system memory and the aperture. If the aperture must be re-enabled, use the 'Change Configuration' window to select a choice. If this method is not successful, then remove the device that is competing for memory such as a system Micro Channel adapter or system memory. Removal of system memory may degrade the system performance. If the aperture has been allocated an address range and it results in a reduction of usable system memory (with Micro Channel memory adapter) then the aperture can be disabled. You must fix conflicts before you use the adapter.
     <"Address at 15 MB (F00000h)>,14, 13, 12, 11, 10, 9, 8, Disabled

Video Arbitration Level
   Selects the arbitration level the adapter uses to transfer data. You must fix conflicts before you use the adapter
        <"Arbitration level 13">, 12, 11, 10, 9, 8, 14, 7

Video Fairness
   Selects the Bus Arbitration Fairness. When Bus Arbitration Fairness is set it controls whether the adapter will release control of the bus when it has been using it exclusively. Normally, the field should be set to <On>.
        <"Fairness On">, Fairness Off

ADPItem 1 ROM Address Range
        Address of the 8K block of memory that is assigned to the adapter. Only one XGA or XGA-2 Display Adapter will have the ROM assigned, and any other XGA or XGA-2 Adapter installed will share that address range. You must fix conflicts before you use the adapter.

Content created and/or collected by:
Louis F. Ohland, Peter H. Wendt, David L. Beem, William R. Walsh, Tatsuo Sunagawa, Tomáš Slavotínek, Jim Shorney, Tim N. Clarke, Kevin Bowling, and many others.

Ardent Tool of Capitalism is maintained by Tomáš Slavotínek.
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