DFI 486SX-20/25UNB AIO
Logs
chipChipset
cpuSocket
Empty
speedFSB speeds
20MHz25MHz
moboForm factor
LPX (max 229 x 330 mm)
dimDimensions
330mm x 218mm
ramMax VRAM size
1MB
chipCache
None/Integrated in the CPU
ramMax RAM size
16MB
ramRAM type
72-pin FPM
pwrPSU connector
AT (6-pin P8 + 6-pin P9)
connI/O ports
1x 
AT Keyboard
1x 
Floppy interface
1x 
IDE interface
1x 
PS/2 mouse
1x 
Parallel
2x 
Serial
1x 
VGA
cardExpansion slots
1x 
16-bit ISA
wrench Known issues
  • Leaky Ni-Cd clock battery

The Ni-Cd battery may be leaking, risking damage to PCB layers & nearby components. Promptly remove the battery & clean corrosion/alkaline salts from the board. Use white vinegar to dissolve salts, but exercise caution as vinegar can corrode exposed metals. A thorough examination & repair may be needed. Replace battery with guide: https://github.com/wiretap-retro/Not-A-Varta

  • Expansion slots are on proprietary riser

The listed slots are on the riser card that came with the motherboard.
If you have this board make sure you have the riser for it.

Last updated 2025-06-24T18:38:13Z
Board info score is 7.7/10
bios 0 BIOS files available

vendor AMI - 1 entry

POST string
Note
Core Ver.
BIOS Ver.
Logs
POST string
Note
Core version
BIOS version
Logs
drv 14 drivers available
Name
Version
OS support
Arch
Size
Filename
Name
Version
1992-01-15
OS support
Windows 3.0 Windows 3.1x
Arch
x86
Size
504.9KB
Filename
Name
Version
1991-10-29
OS support
Windows 3.1x
Arch
x86
Size
397.5KB
Filename
Name
Version
1991-12-06
OS support
Windows 3.0 Windows 3.1x
Arch
x86
Size
399.3KB
Filename
Name
Version
4.0.953
OS support
Windows 9x
Arch
x86
Size
18.4KB
Filename
Version
OS support
Arch
Size
Filename
Version
OS support
Windows 3.1x
Arch
x86
Size
545.2KB
Filename
Version
OS support
Windows 3.1x
Arch
x86
Size
543KB
Filename
Version
OS support
Windows 3.1x
Arch
x86
Size
541.7KB
Filename
Version
OS support
Windows 3.1x
Arch
x86
Size
541.6KB
Filename
Version
OS support
Windows 3.1x
Arch
x86
Size
621.6KB
Filename
Version
OS support
Windows 3.1x
Arch
x86
Size
1.1MB
Filename
Version
OS support
Windows 3.1x
Arch
x86
Size
1.1MB
Filename
Version
OS support
Windows 3.1x
Arch
x86
Size
1MB
Filename
Version
OS support
Windows 3.1x
Arch
x86
Size
1MB
Filename
Version
OS support
Windows 3.1x
Arch
x86
Size
989.7KB
Filename
doc 1 board document available
Release date
File
Logs
Release date
File
Logs
Chip
Release date
File
Logs
Chip
Release date
File
Logs
Chip
Release date
File
Logs
Chip
Release date
1990
File
Logs
Chip
Release date
1996-08-09
File
Logs
Chip
Release date
1996-05-15
File
Logs
Chip
Release date
File
Logs
Chip
Release date
File
Logs
Chip
Release date
File
Logs
Chip
Release date
File
Logs
Chip
Release date
File
Logs
Family
Release date
File
Logs
Family
Release date
1995-12
File
Logs
Family
Release date
1989-04
File
Logs
Family
Release date
1990
File
Logs
Family
Release date
1992-10
File
Logs
Family
Release date
1992-02
File
Logs
image1 Image 1 of 2 (Microhouse)
image2 Image 2 of 2

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