So they figured out that all you have to do is heat up those big Dallas bricks and inside is a crystal, a packaged IC and the little tiny battery you can just snip out and replace with a 2032 holder. Supports my point that a lot of 'replacement parts' for unobtainable stuff are shuffling deck chairs and people need more net-new designs.
That's a new trick? I've got one or two industrial SBCs lying around here where I have done this before they were truly "retro". I dremeled and hot-glued the socket on top of the brick but same difference. I experimented a bit around with where to cut, you can't tell me people just figured that out? I could swear I read websites on this back in the day even. These even gave me the idea to begin with.
Otherwise, somebody is just gonna shove in some modern microcontroller or other into that role, sooner or later. It's been like this with the ease and low cost of pcb manufacturing in recent years - somebody works out a way to use old parts in new designs, and the chinese stockpiles just up and collapse a few months later. For many parts, they are simply not that big. Always kinda sucks to come back to an old project and find out old but still easily to obtain parts suddenly have become unobtanium/are being scalped on ebay because some guy made a github project and some other guy made a youtube video about it. Last few months when I played around with my Z180 again I just went ahead, took some money into my hand and just stockpiled some ICs I thought I might need/want eventually. It's gotten kinda bad, really.
Bought a set of new stock Samsung brand RAM
I'd rotate the old RAM back in now because if the new ones are defective (which is a possibility if you cannot test them) you might have added another error source. I'm not familiar with that particular computer but for many systems of that vintage these negative voltage rails have very specific functions and are not critical. It does sound like your power supply needs to be recapped though. If you fix the power supply, these rails are usually served by simple 79xx regulators. Check if they are still ok, they might need to be replaced too. (e.g. -12V was necessary to do serial and people tinkering around might have shortened that rail out and blown up the regulator. There was usually not much in the way of protection.)
PicoPSUs, at least the original ones, are good replacement power supplies for these old computers in my experience. You can remove the ATX plug and just solder wires and a switch on. (or do fancy crimp connectors if you are so inclined, usually not really necessary though) In a pinch there are only few of these old computers that cannot reliably be powered by one. I'd go with an original one because not all have the -5V and -12V legacy rails that are not needed in modern computers. If anyone uses a PicoPSU as power supply, depending on the hardware you use be careful to not switch the system on and off quickly, but always leave it for a few seconds. Because of the nature of PicoPSUs and how they work, some stuff your system might have might begin to oscillate or latch up if you toggle power quickly and this might damage stuff. Otherwise I really like them, combined with a quality 12V power supply they are a cheap, handy and universal way to hook any system up.
