Here we have a Cyrix 486DLC cpu upgrade on an Elecom interposer. The CPU is also socketed and can be removed. The DLC CPU’s add 486 instructions to a 386 base CPU this has a 33Mhz clock speed (not clock doubled) They are a good way to get 486 instructions for a 386 machine as a cheap upgrade. This was imported from Japan and likely used as a PC98 upgrade. I don’t have details of what the interposer is for but the CPU is tested working.
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