PCChips M4xx (Forex)
Also known as: MICRO EQUIPMENT CORPORATION FOREX 486 VESA (Rev. VL 421A/422)
Form factor
Baby-AT (max 220 x 330mm)
PSU connector
AT-Style (P8-P9)
Chipset
Chipset parts
Forex FRX46C421A Forex FRX46C422
Dimensions
330mm x 218mm
CPU platform
486
Supported FSB speeds
20MHz, 25MHz, 33MHz, 50MHz
Cache
64 KB , 128 KB , 256 KB
Supported RAM size
32 MB
Supported RAM type
30-pin SIMM
I/O ports
N/A
Expansion slots
2x 
32-bit VLB
1x 
8-bit ISA
7x 
16-bit ISA

Known issues:

  • Leaky Ni-Cd clock battery.

    Remove the Ni-Cd battery as soon as possible and neutralize the leakage using white vinegar. Some more in-depth look may be needed to properly fix the motherboard. The battery can then be replaced using this https://github.com/wiretap-retro/Not-A-Varta.

Notes

FR46C521A Chipset

Last updated 2022-10-21T11:02:22Z
drv Drivers: not available
BIOS images: no files available
Manuf.
POST String
Note
Core Ver.
BIOS Ver.
AMI
40-P301-001437-072594-DGREEN-H
072594
doc Documentation: 1 entry
Model
Speed
FSB
Voltages
L1 Cache
L2 Cache
L3 Cache
Core
Process
TDP
Intel i486 DX 50
50MHz
50MHz
5V
8KB
-
-
P4
1000nm
-
Intel OverDrive 486SX2-66 (PGA169)
66MHz
33MHz
5V
8KB
-
-
P23T
-
-
Intel OverDrive 486DX2-66 (PGA169)
66MHz
33MHz
5V
8KB
-
-
P4T
-
-
Intel OverDrive 486DX2-66 (PGA168)
66MHz
33MHz
5V
8KB
-
-
P4T
-
-
Intel i486 DX2 66
66MHz
33MHz
5V
8KB
-
-
P24
800nm
5W
Intel i486 SX 33
33MHz
33MHz
5V
8KB
-
-
P23
1000nm
-
Intel i486 DX 33
33MHz
33MHz
5V
8KB
-
-
P4
1000nm
-
Intel OverDrive 486SX2-50 (PGA169)
50MHz
25MHz
5V
8KB
-
-
P23T
-
-
Intel OverDrive 486DX2-50 (PGA169)
50MHz
25MHz
5V
8KB
-
-
P4T
-
-
Intel OverDrive 486DX2-50 (PGA168)
50MHz
25MHz
5V
8KB
-
-
P4T
-
-
Intel i486 DX2 50
50MHz
25MHz
5V
8KB
-
-
P24
800nm
-
Intel i486 SX 25
25MHz
25MHz
5V
8KB
-
-
P23
1000nm
-
Intel i486 DX 25
25MHz
25MHz
5V
8KB
-
-
P4
1000nm
-
Intel i486 SX 20
20MHz
20MHz
5V
8KB
-
-
P23
1000nm
-
No NPUs listed.

Disclaimer

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