CO700115 REV. 2B with Piggyback RAM expansion.

ST & STM motherboards.
PhilC
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Re: CO700115 REV. 2B with Piggyback RAM expansion.

Post by PhilC » Mon Dec 24, 2018 4:57 pm

Well done, if it's one thing I've learned, it's when you start to get Ram problems on an old computer, it's usually a good idea to change the lot and then work out what still might work 😁

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Re: CO700115 REV. 2B with Piggyback RAM expansion.

Post by rubber_jonnie » Wed Dec 26, 2018 10:35 am

Forgottenmyname wrote:
Mon Dec 24, 2018 4:57 pm
Well done, if it's one thing I've learned, it's when you start to get Ram problems on an old computer, it's usually a good idea to change the lot and then work out what still might work 😁
I quite agree, and once I'd tweaked the PLCC socket pins for the MMU and GLUE, and the original memory was gone, booting up gave me a black screen with a white border, so a classic case of no RAM, meaning it looked like everything else was good to go. Just a case of dropping in a known good RAM expansion kit. I may yet install sockets and new de-coupling capacitors, and test with known good RAM to see if I can bring the thing back to life in a more original condition. Still thinking on that one, as it's a very early revision and seems to have no 68R resistors in the CAS/RAS lines, as they were added into the original piggyback RAM expansion.
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