DOS Days

Microstar International, Inc.

MSI was a manufacturer of motherboards for the IBM PC and its compatibles during the DOS era. They also produced OEM boards for Fujitsu-Siemens, HP, Maxdata, and Medion.

The MS-3xxx series was based around the Intel 80386 microprocessor.
The MS-4xxx series was based around the Intel 80486 microprocessor, as well as compatibles from Cyrix and AMD.
The MS-5xxx series was designed for the Intel Pentium P54C/P55C, Cyrix M1/6x86, AMD K5/K6/K6-2, and IDT C6 microprocessors.

MS-3121

Year: 1988
Type: 80386
Form Factor: AT
Power Connectors: AT
Chipset: Chips & Technologies
Slots: 16-bit ISA (6), 8-bit ISA (2)
Memory: 30-pin SIMMs x 8 (4 banks)
BIOS: AMI
Known Board Revisions: v3.0

According to MSI, this was the world's first overclocking 80286 motherboard! It supported an additional CPU in the form of a 386DX-33, and had a 387 coprocessor socket too!

MS-4125

Year: 1993
Type: Socket 3
Form Factor: AT
Power Connector: AT
Chipset: Contaq 82C596 / C&T 82C206
Slots: 7 x 16-bit ISA of which 2 are VESA Local Bus, 1 x 8-bit ISA
Memory: 8 x 30-pin SIMMs (FPM only). Max. 32 MB.
BIOS: AMI
Known Board Revisions: 3.1

The MS-4125 supports both 80486SX, 80486DX and 486 Overdrive processors from 25 MHz up to 50 MHz, and also has the manufacturer's option of having a socketed processor or a surface-mount one.

It also supports up to 256 KB of L2 cache.

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MS-4126

Year: 1993
Type: Socket 3
Form Factor: AT
Power Connector: AT
Chipset: SiS 85C471
Slots: 7 x 16-bit ISA of which 3 are VESA Local Bus
Memory: 8 x 30-pin SIMMs (FPM only). Max. 32 MB.
BIOS: AMI or Phoenix
Known Board Revisions: 2.2

The MS-4126 supports the following CPUs: Intel 80486SX/80486DX/DX2 with clock speeds from 25 MHz up to 66 MHz. Onboard cache support is from 64KB up to 256KB.

Memory is in 2 banks of 4 slots each, and supports 256KB, 1MB or 4MB SIMM DRAM modules.

MS-4131/4131G

Year: 1993
Type: Socket 3
Form Factor: AT
Power Connector: AT
Chipset: ALi
Slots: 7 x 16-bit ISA of which 3 are VESA Local Bus
Memory: 4 x 30-pin SIMMs, 2 x 72-pin SIMMs (max. 64 MB on MS-4131G, 112 MB on MS-4131)
BIOS: AMI, Award or Phoenix

The MS-4131 support the following CPUs: Intel 80486SX/80486DX/DX2 with clock speeds from 25 MHz up to 66 MHz. The MS-4131G additionally supports the Cyrix CX486M7, AMD 486DX, and Pentium Overdrive with internal clock speeds from 20 MHz up to 66 MHz.

The 30-pin SIMM slots act as 1 bank of 4 slots, and the 72-pin slots act as a further 2 banks.

The motherboard comes with onboard cache of either 128KB or 256KB on MS-4131, or up to 512KB on MS-4131G.

The VESA Local Bus can be configured to run with either 0 or 1 wait state.

MS-4132

Year: 1993
Type: Socket 3
Form Factor: AT
Power Connector: AT
Chipset: SiS 85C471
Slots: 7 x 16-bit ISA of which 3 are VESA Local Bus
Memory: 4 x 30-pin SIMMs (FPM only), 2 x 72-pin SIMMs. Max. 96 MB.
BIOS: AMI or Phoenix
Known Board Revisions: 2G, 2.3, 2.4

The MS-4132 supports the following CPUs: Intel 80486SX/80486DX/DX2 and AMD Am486DX/DX2 with clock speeds from 25 MHz up to 66 MHz. Onboard cache support is from 128KB up to 512KB.

Memory is in 2 banks of 4 slots each, and supports 256KB, 1MB or 4MB SIMM DRAM modules.

MS-4134

Year: 1993
Type: Socket 3
Form Factor: AT
Power Connectors: AT
Chipset: ALI M1429 / M1435
Slots: 16-bit ISA (5), VESA Local Bus (2), PCI (3)
Memory: 4 x 30-pin SIMMs, 2 x 72-pin SIMMs (max. 112 MB onboard)
BIOS: AMI
Known Board Revisions: 1.1

This was one of the first ever Socket 3 PCI-based motherboards.

The MS-4134 motherboard supports Intel 80486 SX, DX and DX2 CPUs as well as their AMD counterparts, ranging from 25 MHz up to 66 MHz. It also identifies whether you have installed an S-series CPU, which provide SMM mode - these CPUs can be identified physically with the code "SA5V1X" stamped on them. It also supports the Cyrix M7.

The VESA Local Bus can be driven at <=33 MHz or over 33 MHz, set via 3 jumpers.

The board comes with either 128 KB or 256 KB of cache.

BIOS version AL57, dated 1994-11-19 is the most recent.

Tested maximum bus transfer rates with this board:

Hercules Dynamite 128 31 MB/sec
Matrox Millennium (MGA2064) 31 MB/sec
Elsa Winner 1000 (S3 Trio64V+) 31 MB/sec

MS-4137

Year: 1993
Type: Socket 3
Form Factor: AT
Power Connector: AT
Chipset: ALi M1429
Slots: 2 x 8-bit ISA, 6 x 16-bit ISA of which 3 are VESA Local Bus
Memory: 4 x 72-pin SIMMs (max. 64 MB)
BIOS: AMI
Known Board Revisions: 1.3

This board was also known as the ALi-486G or the VLB 486 AL5.

Supported CPUs include Intel 80486SX/DX, Pentium Overdrive, AMD/Cyrix P23T.

Maximum cache is 256 KB.

MS-4138

Year: ?
Type: Socket 3
Form Factor: AT
Power Connector: AT
Chipset: SiS 85C471
Slots: 7 x 16-bit ISA of which 3 are VESA Local Bus
Memory: 4 x 72-pin SIMMs (FPM only). Max. 64 MB.
BIOS: AMI
Known Board Revisions: 1.3

The MS-4138 supports the following CPUs: Intel 80486SX/80486DX/DX2, Cyrix CX486M7, AMD 486DX, and Pentium Overdrive with clock speeds from 25 MHz up to 66 MHz. Onboard cache support is from 64KB up to 256KB.

MS-4144

Year: 1994
Type: Socket 3
Form Factor: AT
Power Connectors: AT
Chipset: SiS 496/497
Slots: 16-bit ISA (4), PCI (3)
Memory: 4 x 72-pin SIMMs
BIOS: AMI
BIOS Versions: AF53 AF53S AF54S WF53S WF54S
Known Board Revisions: 1.5, 1.6, 2.1, 2.2

BIOS Versions:

  • AF54S - to be used only with boards that have the SST or WinBond flash memory. With other brands, you will have issues with Windows 95's RESTART function. This BIOS version fixes a bug where if COM2 is disabled, "FDC Controller Failed" message is shown on boot. It also added support for AMD Am5x86-P75 (X5-133 MHz) CPU. Also supports Intel DX4 Write-back CPUs. Added option "Hard disk detect delay time". AF54S is now PnP-compatible (AF53 was not). Does not support PS/2 mouse.
  • WF53S - to be used only with boards that have the SST or WinBond flash memory. With other brands, you will have issues with Windows 95's RESTART function. This BIOS version fixes a bug where if COM2 is disabled, "FDC Controller Failed" message is shown on boot. It also added support for AMD Am5x86-P75 (X5-133 MHz) CPU. Also supports Intel DX4 Write-back CPUs. Added option "Hard disk detect delay time". AF54S is now PnP-compatible (AF53 was not). Does not support PS/2 mouse.

This board was also known as the 486-SI1.

MS-5116

Year: 1994
Type: Socket 5?
Form Factor: Baby AT
Chipset: SIS 5511
Slots: none
Memory: 4 banks of 30-pin SIMM. Max 512 MB.
Power Socket: AT (P8/P9)
BIOS: AMI
BIOS Dates:
Latest BIOS Version:
Known Board Revisions:

This was an OEM board with onboard VGA. It has a single ISA riser slot for expansion purposes.
Supported CPUs were the Pentium 75 up to 133, and the Cyrix M1

MS-5117

Year: 1994
Type: Socket 7
Form Factor: Baby AT
Chipset: VIA Apollo Master
Slots: 4 x 16-bit ISA, 3 x PCI
Memory: 2 banks of 30-pin SIMM (FPM or EDO). Max 512 MB.
Power Socket: AT (P8/P9)
BIOS: Award v4.50PG
BIOS Dates: 04/24/96, 09/08/95
Latest BIOS Version: W976 (for Apollo Plus chipset), W97 (for Apollo Master chipset)
Known Board Revisions: 2.0

The MS-5123 supports the Cyrix 6x86 CPUs from P120+ up to P166. It also supports Pentium P54C 75-200 MHz, AMD K5 90 and 100 MHz. CPU voltages supported are 3.38V and 3.52V with available clock multipliers of 1.5x, 2x, 2.5x and 3x. The FSB can be run at 50, 60 or 66 MHz.

The board can support 256KB, 512KB and even 1MB of cache, with burst mode for 256KB only.

MS-5118

Year: 1994
Type: Socket 7
Form Factor: Baby AT
Chipset: SIS 5511
Slots: 4 x 16-bit ISA, 3 x PCI
Memory: 4 banks of 72-pin SIMM (FPM or EDO). Max 512 MB DRAM.
Power Socket: AT (P8/P9)
BIOS: AMI WinBIOS (AMI94)
BIOS Dates:
Latest BIOS Version:
Known Board Revisions:

Supports 100 MHz FSB. Comes with either 256KB, 512KB or 1MB of L2 cache onboard. CPU support is Pentium 75 through 133 MHz.

This board is identical to the MS-5122, except the cache package. This board uses asynchronous cache chips, whereas the MS-5122 uses two PLB packages.

MS-5119

Year: 1994
Type: Socket 7
Form Factor: Baby AT
Chipset: Intel 430FX
Slots: 4 x 16-bit ISA, 3 x PCI
Memory: 4 banks of 72-pin SIMM (FPM or EDO). Max 128 MB DRAM.
Power Socket: AT (P8/P9)
BIOS: AMI WinBIOS (AMI94)
BIOS Dates: 10/10/94, 07/15/95
Latest BIOS Version: A37E
Known Board Revisions:

CPU support is Pentium P54C 75 MHz up to 133 MHz. Core multipliers are 1.5x, 2x, 2.5x and 3x. Front Side Bus speeds supported are 50, 60 and 66 MHz. Comes with either 256KB or 512KB of L2 cache onboard.

BIOS version A37E adds support for Pentium MMX up to 200 MHz. This CPU requires a voltage regulator to work with this board, as the motherboard only natively supports CPU voltages of either 3.4V and 3.5V.

MS-5120

Year: 1995
Type: Socket 5/7
Form Factor: Baby AT
Chipset: Intel 430FX (Triton)
Slots: 4 x 16-bit ISA, 3 x PCI
Memory: 4 banks of 30-pin FPM or EDO SIMM (max. 128 MB)
BIOS: AMI
BIOS Dates: 02/01/96, 07/04/96
Latest BIOS Version: A37E
Known Board Revisions: 1.0, 1.7

This is a Pentium motherboard from Microstar. It supports speeds of 75, 90, 100, 120 and 133 MHz. CPU voltage selections are 3.4V and 3.5V only, but does support a voltage regulator module that plugs into a 30-pin connector beside the CPU socket. CPU multiplier selections available are 1.5x, 2x, 2.5x and 3x.
The MS-5120 supports the Cyrix 6x86 CPU, but requires the D45H2A voltage regulator.
It also supports AMD K5 up to 100 MHz.

It comes with 256 KB of L2 cache onboard. Supported bus speeds are 50, 60, and 66 MHz.

Tested maximum bus transfer rates with this board:

Hercules Dynamite 128 88 MB/sec
Matrox Millennium (MGA2064) 77 MB/sec
Elsa Winner 1000 (S3 Trio64V+) 60 MB/sec

MS-5122

Year: 1996
Type: Socket 7
Form Factor: Baby AT
Chipset: Intel 430FX
Slots: 4 x 16-bit ISA, 3 x PCI
Memory: 4 banks of 72-pin SIMM (FPM or EDO). Max 128 MB DRAM.
Power Socket: AT (P8/P9)
BIOS: AMI WinBIOS (AMI94)
BIOS Dates: 10/10/94, 07/15/95
Latest BIOS Version: A37E
Known Board Revisions: 1.0

This board is identical to the MS-5118 apart from the L2 cache package. On the 5118 it's asynchronous, and on this one it's PLB.

CPU support is Pentium P54C 75 MHz up to 133 MHz. Core multipliers are 1.5x, 2x, 2.5x and 3x. Front Side Bus speeds supported are 50, 60 and 66 MHz. Comes with either 256KB or 512KB of L2 cache onboard.

MS-5123

Year: 1996
Type: Socket 7
Form Factor: Baby AT
Chipset: SiS 5513
Slots: 4 x 16-bit ISA, 3 x PCI
Memory: 4 x 72-pin SIMMs
BIOS: Award
BIOS Dates: 01/08/96, 04/16/96
Known Board Revisions: 1.0

The MS-5123 supports the Cyrix P120+ and P150+ 6x86 CPU. This motherboard has embedded graphics in the form of the SiS 6502 (requires a cable though, as not on the backplane). It also supports a PS/2 mouse (again, a cable is required).

The MS-5123 comes with 256 KB of L2 cache onboard.

MS-5124

Year: 199?
Type: Socket 7
Form Factor: Baby AT
Chipset: SIS 5511
Slots: 4 x ISA, 4 x PCI
Memory: 4 banks of 72-pin FPM DRAM. Max 256 MB.
BIOS: Award or AMI WinBIOS
BIOS Dates: 01/08/96, 04/16/96
BIOS Versions: AMI: 1.0 Award: 1.0 1.1 1.2
Known Board Revisions: 1.0

Supports Pentium P54C from 75 MHz up to 166 MHz, , Cyrix 6x86 (M1) up to 120 MHz, AMD K5 up to 166 MHz. FSB speeds are 50, 60 or 66 MHz. Cache is either 256 or 512 kB.

BIOS Versions:

  • Award 1.0 - Added support for Cyrix 6x86 CPU, PS/2 mouse and the MS-3805 NCR 810 PCI SCSI controller.
  • Award 1.1 - As above, but does *not* support PS/2 mouse
  • Award 1.2 - unknown

MS-5128

Year: 1996
Type: Socket 7
Form Factor: Baby AT
Power Connectors: AT
Chipset: Intel
Slots: 4 x ISA, 4 x PCI
Memory: 4 x 72-pin SIMM
BIOS: Award or AMI
BIOS Dates:
BIOS Versions: AMI BIOS: AH76 AH77 AH78 AWARD BIOS: WH77 WH78 WH79
Known Board Revisions: 1.1

The MS-5128 supports the Cyrix 6x86 CPUs from P120+ up to P166+, as well as Pentium MMX CPUs.

BIOS Versions:

  • AH76 - Added support for 360KB and 720KB floppy drives, fixed problem of not being able to boot from BOOT ROM. Added option to boot from SCSI.
  • AH77 - Fixed issue where 128 MB memory installed but only used 32 MB. Added support for AMD-K5/PR166, AMD K6/PR2-166 to PR2-200, and Intel P55C-MMX/233 CPUs.
  • AH78 - Fixed issue when using AMD K6 CPU with Matrox Mystique with 4MB memory (system would hang on warm boot from a DOS prompt).
  • WH77 - Disabled "write gathering function" for Cyrix CPU to solve problems with some VGA cards such as SiS 202 and S3. Fixed 16-bit I/O decode failure in Windows 95 SCT 5.20. Added option to boot from SCSI. Added option for CD-ROM - this has to be set for some types of CD-ROM which show a warning in Windows 95.
  • WH78 - Now Y2K-compliant. Fixed system hang in Windows 95 when Intel Ether Express Pro 100 and Diamond Stealth 64 are both installed. Now supports AMD PR166 CPU.
  • WH79 - Added support for LS-120 floppy drive, AMD K5/PR2-166 to PR2-200 CPUs, as well as Intel P55C-MMX/233 CPU.

MS-5129

Year: 1996
Type: Socket 7
Form Factor: Baby AT
Power Connectors: AT
Chipset: Intel 430VX
Slots: 3 x ISA, 4 x PCI
Memory: 4 x 72-pin SIMM and 1 x 168-pin DIMM. Max 128 MB.
BIOS: Award or AMI
BIOS Versions: AMI BIOS: AI75 AWARD BIOS: WI7A
Known Board Revisions: 1.2, 2.0

CPU support: Intel P54C (75 - 166 MHz), Pentium MMX P55C (166 - 233 MHz), Cyrix 6x86 (P120+ to P166+), AMD 5k86 or K6 (P75 to P200).
FSB speeds supported are 50, 55, 60 and 66 MHz.

430VX chipset supports the very early SDRAM - either 16MB (8 chips on 1 side) or 32MB (16 chips on 2 sides).

The board comes with either 256 KB or 512 KB of L2 cache (256 KB onboard + 256 KB on cache module COAST spec 1.3 or later). Maximum cachable area is 64 KB.

MS-5136

Year: 1996
Type: Socket 7
Form Factor: Baby AT
Power Connectors: AT and ATX
Chipset: Intel 430VX
Slots: 4 x ISA, 4 x PCI
Memory: 4 x 72-pin SIMM (FPM or EDO). Max 128 MB.
BIOS: Award or AMI
BIOS Versions: AMI BIOS: AI75 AI78 AWARD BIOS: WI7A WI7C
BIOS String: 05/14/97-i430VX-2A59GM49C-00
Known Board Revisions: 1.0, 1.3

Supports Pentium (75 MHz to 200 MHz, AMD K5 (75 and 90 MHz), and Cyrix M1 (120 to 166 MHz). CPU core voltage choices are 2.8V, 3.38V and 3.52V.

Comes with a COAST slot to expand L2 cache from 256 KB to 512 KB. Maximum cacheable area with the 430VX chipset is 64 MB. It is possible that without the COAST slot populated, maximum cacheable area drops to 32 MB.

BIOS Versions:

  • AI78 - Fixed these issues: In Windows 95, if the SUSPEND button is pressed twice, system will hang. - In Windows 95, even if Power Management is enabled, the SUSPEND button will not appear. - In Windows 95, 3COM 3C509B ISA PnP Network Card will have a warning message, and will not function properly. - When booting with 3COM 3C590 PCI Network Card boot ROM, the message Press H to boot from hard disk will not appear.
  • WI7C - Adds Year 2000 compliance.

MS-5137

Year: 1996
Type: Socket 7
Form Factor: Baby AT
Power Connectors: AT (P8/P9)
Chipset: Intel 430VX
Slots: 4 x ISA, 3 x PCI
Memory: 4 x 72-pin SIMM (FPM or EDO). Max 128 MB.
BIOS: Award or AMI
BIOS Versions: AMI BIOS: AI75 AI78 AWARD BIOS: WI7A WI7C
Known Board Revisions:

Almost identical to MS-5136 motherboard. Supports Pentium (75 MHz to 200 MHz, AMD K5 (PR75 and PR90), and Cyrix 6x86 (PR120 to PR166).

BIOS Versions:

  • AI78 - Fixed these issues: In Windows 95, if the SUSPEND button is pressed twice, system will hang. - In Windows 95, even if Power Management is enabled, the SUSPEND button will not appear. - In Windows 95, 3COM 3C509B ISA PnP Network Card will have a warning message, and will not function properly. - When booting with 3COM 3C590 PCI Network Card boot ROM, the message Press H to boot from hard disk will not appear.
  • WI7C - Adds Year 2000 compliance.

MS-5139

Year: 1995
Type: Socket 7
Form Factor: Baby AT
Chipset: SIS 5511
Slots: none
Memory: 4 banks of 30-pin SIMM. Max 512 MB.
Power Socket: AT (P8/P9)
BIOS: AMI
BIOS Dates:
Latest BIOS Version:
Known Board Revisions:

MS-5143

Year: 1996
Type: Socket 7
Form Factor: ATX
Power Connectors: ATX
Chipset: Intel 430VX TR9 (Triton II)
Slots: 4 x ISA, 4 x PCI
Memory: 4 x 72-pin SIMM (FPM or EDO) and 2 x 168-pin DIMM. Max 128 MB.
BIOS: Award or AMI
BIOS Versions: AMI BIOS: AI78 AWARD BIOS: WI7C
Known Board Revisions: 1.0, 2.0

This board supports the faster SDRAM via its DIMM slot.

CPU support: Intel Pentium (75-200 MHz), Cyrix M1 (120 - 166 MHz) and AMD K5 (75 - 166 MHz). CPU Core voltages supported are 3.52V and 3.38V for single-voltage CPUs, and for dual-rail CPUs (core and I/O), core voltages are 2.5V, 2.8V and 2.9V.

The images below show the much more rare Revision 1 of this board, courtesy of Pawel Jucha. It has the two 168-pin DIMM sockets as well as both an AT and ATX power connector. This implies that the Rev.2 version is possibly a cost-reduced version of the MS-5143.

Thanks to DOS Days contributor Pawel Jucha for the last 4 images below.

More Images

MS-5144

Year: 199?
Type: Socket 7
Power Connector: AT
Form Factor: AT (250mm x 220mm)
Chipset: SiS
Slots: 4 x 16-bit ISA, 4 x PCI
Memory: 2 x 72-pin SIMM slots, 2 x 168-pin DIMM slots. EDO RAM supported.
Known Board Revisions:

MS-5146

Year: 1996
Type: Socket 7
Form Factor: ?
Power Connector: AT
Chipset: SiS 5571
Slots: 4 x 16-bit ISA, 4 x PCI
Memory: 4 x 72-pin SIMM slots (Max. 256 MB EDO)
BIOS: Award or AMI
BIOS Versions: AMI BIOS: 1.1 AWARD BIOS: 2.0
Known Board Revisions: 1.1

This board accepts FSB speeds up to 75 MHz. It supports Intel Pentium 75 to 200, AMD CPUs from 75 up to 166 MHz, or Cyrix from 120 up to 200 MHz. It does not support AMD K6-2 333 to 550.

CPU voltage selection options are 3.3V, 3.38V or 3.52V, with core voltage support for 2.8V, 2.9V or 3.0V.

L2 cache can be either 256 KB or 512 KB.

Some earlier versions of the BIOS will crash while detecting the processor frequency.

MS-5169

Year: 1999
Type: Socket 7
Form Factor:
Power Connector: ATX
Chipset: ALi Aladdin V
Slots: 3 x ISA (16-bit), 4 x PCI, 1 x AGP
Memory: 3 x 168-pin DIMM, 768 MB max.
BIOS: AMI 1992+
Latest BIOS Version: 3.7 (dated 8th Sep 2000)

Supports Intel Pentium and Pentium MMX, Cyrix 6x86/MX, AMD K5, AMD K6 and K6-2 and IDT C6.
CPU voltages supported from 2.1V up to 3.5V.
Bus speeds from 66 MHz up to 100 MHz.

User Manual
Jumper Settings (v1)
Jumper Settings (v1 to v4)

MS-5182

Year: 1999?
Type: Socket 7
Form Factor: ATX
Power Connector: ATX
Chipset: ALi Aladdin V
Slots: 1 x ISA (16-bit), 3 x PCI
Memory: 2 x 168-pin DIMM
BIOS: AMI
Known Board Revisions: 1 (see picture)

This board was designed for OEMs, and came with an integrated ATI Rage Pro Turbo 3D accelerator.

MS-5191

Year: 1999?
Type: Socket 7
Form Factor: ATX
Power Connector: ATX
Chipset: ALi Aladdin V
Slots: 3 x PCI
Memory: 2 x 168-pin DIMM
BIOS: AMI
Known Board Revisions: 1.1 (see picture)

Possibly MSI's first motherboard that did away with ISA slots. It came with integrated Sound Blaster audio and 3D accelerator graphics (not sure what brand).