Vintage 386 VLB Baby AT Motherboard - AMD Am386DX-40 CPU & IIT 3C87 FPU Coprocessor
Rare transitional 386-class motherboard featuring 32-bit VESA Local Bus (VLB) architecture and the OPTi 82C495SX chipset. Equipped with an onboard AMD Am386DX-40 processor, an installed IIT 3C87-40 hardware math coprocessor, 256KB of L2 cache, and an open PGA-132 upgrade socket for Cyrix Cx486DLC processors. Ideal for authentic MS-DOS and Windows 3.1 retro computing setups.
Key Specifications:- Platform / Architecture: 386 VLB (VESA Local Bus) / ISA- Chipset: OPTi 82C495SX System Controller + OPTi F82C206Q Peripheral Controller- Primary CPU: AMD Am386DX-40 (soldered PQFP package, 40 MHz core / 40 MHz FSB)- Math Coprocessor (FPU): IIT 3C87-40 (Integrated Information Technology Super Math, PGA-68 installed)- Upgrade CPU Socket: 132-pin PGA socket (supports Cyrix Cx486DLC, TI486DLC, and Intel 386DX via jumpers)- L2 Cache: 256KB Write-Back Cache installed (8x ISSI IS61C256A-20N SRAM chips + TAG RAM in sockets)- Memory: 8x 30-pin SIMM sockets (supports FPM DRAM)- Expansion Slots: * 1x 32-bit VLB (VESA Local Bus) slot * 6x 16-bit ISA slots (7 ISA slots total, 1 shared with VLB)- BIOS: AMIBIOS 386DX ISA BIOS in socket (Label: AA0981641)- Power Management: Lance Corp. LT38C41 Green PC controller- Keyboard Port: Standard 5-pin DIN (AT style)- Power Connector: Standard 12-pin AT power connector (P8/P9)- Form Factor: Baby AT (approx. 8.7" x 9.8" / 22 cm x 25 cm)
Package Includes:- 1x 386 VLB Motherboard with soldered AMD Am386DX-40 CPU- 1x IIT 3C87 Math Coprocessor (installed in socket)- 8x ISSI 256KB Cache SRAM Chips (installed in sockets)
