Motherboard Failure

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RiverBoa99
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Motherboard Failure

Post by RiverBoa99 »

So I installed a V20, Tandy Mod, and a PC-Sprint on a cherry board I picked up from Computer Reset. It worked for about 10 minutes and crashed after I tried to run Civilization on it.

When I rebooted, it would only play a single low audio tone and would not boot. I spent a little time reinserting all the old chips, but even after doing all that, I was still getting the same error.

Luckily, I still had a few spare PCjr boards, so I was able to transplant all the upgrades into a different motherboard and it all worked fine. I've done some stress testing and played a few more higher powered games, but have not been able to produce the same issues.

I really want to see if Civilization will run on this beast, but I'm leery about trying to run it again for fear it'll burnout the mother board.
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chuckphd53
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Re: Motherboard Failure

Post by chuckphd53 »

First thing that comes to mind is the PCSprint board, and possible issue with the connection to the MB, this is the main timing focus...
I know some installs have issues with damaged the pins plated thruhole connections getting damaged when removing the original chip.
This damage will break the connection from the bottom side of the MB to the topside VIA's.
A quick fix is to take some stranded 26 awg wire open the strands and take 1 strand (very small) and insert it thru the hole
carefully bending it over each side, top and bottom, cutting off the excess so as not to short any adjoining pins.
then insert a socket and solder carefully.

the Tandy mod should not produce a non-working system, and since the V20 works in the new system you should be good
So I would focus on the PC Sprint chip socket, remove and clean all the holes, inspect with eye loupe and see if there are any
obvious issues...
“I never commit to memory anything that can easily be looked up in a book.” (AE)
RiverBoa99
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Re: Motherboard Failure

Post by RiverBoa99 »

Think there’s any chance I blow the board again?
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chuckphd53
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Re: Motherboard Failure

Post by chuckphd53 »

I dont see how software can make this happen.
Try running with the pcsprint off, then turn it on... should be fine..
I think you had a solder issue and the other board is still good with some investigative work...
“I never commit to memory anything that can easily be looked up in a book.” (AE)
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