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anybody have a idea what this hw modification is supposed to do?

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First post, by treeman

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this is a 486 vlb motherboard with no cache, it is a dca tech (direct cache access) if it makes any difference.

I don't remember if this board ever booted but it is not posting now and I noticed a hardware mod on what I think is one of the buffers or hex inverter near the cpu. I am very curious what it is supposed to do, and if I reverse it maybye it will boot?

The chip in question is a QUAD 2-INPUT AND GATE FAST SCHOTTKY TTL

so from my poor understanding it is a gate chip that lets data through 1 way but not back the other?

anyway here is 2 pictures, one unmodified and second where I circled the 2 jumper cables that have been attached to the chip, the original pin removed and rerouted to a resistors

IMG-20190718-094758.jpg

Draw-Over-Photo1563407458173.png

Reply 1 of 7, by Tiido

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This is a factory fix and reverting it will most probably cause nothing to work at all. It probably exists to correct some timing issue or maybe an outright routing mistake.

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Reply 2 of 7, by retardware

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I guess just some factory fix for the first series PCB.
I guess there happens nothing special. Just some pull-up of one gate input pin.
What chipset, if I may ask?

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