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Unfortunately, a solid red OK light indicates the controller has failed a low-level self-diagnostic and the operating system is not even starting.
- Remove the RAM back up battery.
- Give the controller a few firm raps on the table.
- Blow the controller out with compressed air.
- Disassemble the memory daughtercard from the CPU.
- Give it a good bath with isopropyl alcohol and let it dry.
- Inspect the backplane pins.
- Put the controller in a freezer for a couple of hours.
If those don't at least get you to a flashing red OK LED, then see what your recourse is with the eBay seller, or promote the controller to dust cap duty.