Here is a Buffalo HDL-20W-B Interposer with a Texas Instruments TX486DLC/E-40GA soldered in place. Note this is not a socketed interposer the chip is soldered. This was imported from Japan and would have been an upgrade for the PC98 market. I don’t have the details of what the interposer does those details are likely online if searched. However the CPU upgrades a 386 machine and adds 486 instructions. The DLC CPU’s are generally not clock multiplied. It is marked up with 40 which means the CPU supports 40Mhz All pins are straight and the interposer is in good condition. Sold as seen
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