486DX2/66 486 CPU Processor Upgrade Card 92427-1 OPTi Chipset ISA 48.49802

486DX2/66 486 CPU Processor Upgrade Card 92427-1 OPTi Chipset ISA 48.49802

This is a 486DX2-66MHz processor upgrade card designed for ISA-bus systems. The board carries a 486DX2 CPU in a PGA socket running at 66MHz and uses an OPTi chipset for system logic. Multiple onboard memory banks accommodate DIP-style RAM modules. It connects to the host system via a standard 16-bit ISA edge connector.

Specifications & What's Included

• Part Number: 92427-1
• Secondary Part Number: 48.49802.001
• CPU: 486DX2 at 66 MHz (486DX2SA66)
• CPU Socket: PGA (Pin Grid Array)
• Chipset: OPTi
• Bus Interface: 16-bit ISA
• Memory: Multiple onboard DIP memory sockets (several populated)
• Jumper JP17: 33M clock selection — pins 1-2 or 3-4
• Country of Manufacture: Taiwan R.O.C.
• Includes: Card only — no cables or accessories

Applications

486 CPU processor upgrade cards like this one were produced in the early-to-mid 1990s as a way to boost the performance of existing ISA-bus PC systems without replacing the entire motherboard. A host system would accept this card through its ISA slot, offloading processing duties to the faster 486DX2-66MHz CPU onboard. The 486DX2 doubled the internal clock speed relative to the bus — running its core at 66MHz while communicating with the system bus at 33MHz — which gave a meaningful performance increase over slower 486SX or 486DX-33 systems of the era. OPTi was a major supplier of PC chipsets throughout the 486 generation, and their logic chips appeared on numerous third-party upgrade and processor boards of this period. These cards are now primarily sought by vintage computing enthusiasts and collectors maintaining or restoring period-correct ISA-bus PCs from the early 1990s.