This one is a bit of a conundrum. I found the motherboard and CPU in the stuff in our attic, so I assume it belonged to my dad a long time ago. It is in need of some board-level repair though so it might take a bit of careful work to get it to function properly.
The board specifically needs a new voltage regulator to be installed, and a couple of 10v 1000uf capacitors that bulged to be replaced. I might install Windows 95 or 98 on it, but I also wanna see how it would run various Linux distributions, as well as Haiku. It's a Pentium II class CPU, so I assume it would handle at least some of these things well enough.
This has been what I have spent the last month or so working on, with honestly fantastic results.
The board was exactly as broken as I thought, in exactly the ways that I thought, PLUS MORE. Late in October I returned to the project out of curiosity and boredom, and fitted a new mosfet in the CPU power delivery section. Yeah, back in like... 2021 or whenever I made the last earnest attempt to fix the board, I had a fundamental misunderstanding of what that component was... not a regulator. That explains the sparks when I tried tying the tab to ground. I still had about four of the CEB6030L that I bought back then the last time I made a mess of the thing, and now with better tools available, I soldered a new one on.
And then it promptly attempted to set itself on fire. Amazing!
I pulled the CPU out and with my new multimeter, another tool added to my arsenal in recent times, I checked the new mosfet. Dead short. Then I pulled out the CPU and checked the voltage that was going to the socket.
Five. Entire. Volts.
That is NOT good. But it gave me some clues, of course. I checked the CPU next, and across VCORE and ground was also a dead short, less than an ohm. That may even be the internal resistance of my probes, so very clearly dead. Rest in peace, 400MHz K6-2. More CPUs ordered from eBay, another 400MHz CPU and a 300MHz one too, which was going to be my testing CPU as that way I wouldn't burn out the faster one if my repair didn't stick. I also placed an order for some 1000uf low-ESR capacitors to replace the ones which had clearly gone bad near the CPU socket. That does beg the question, though. What failed first, back in the day? The CPU was clearly bad, that mosfet burned up, and the capacitors were bulged and leaking... so... If the capacitors failed first, as this board was sold early in the capacitor plague era, it could have put more load on the mosfet due to not having the bulk capacitance to handle transients, which may have killed the mosfet, and then let 5v into a 2.2v CPU which caused THAT to die, and that just caused a chain reaction that set everything on fire.
That's my theory, anyways. Fast forward. Now we are at the beginning of November, and my new CPUs have arrived. A fresh mosfet is installed, capacitors are installed, I had just gotten some cheap monitors at a local thrift shop for about $5 apiece if you break it down. So I get down on the floor and set up the board on top of a cardboard box, draged out a power supply and a keyboard, a hard drive I had from a data recovery project for a family friend, an optical and floppy drive I got out of an untested lot, and borrowed some ribbon cables from my hacked up IBM M50. Hela lent a 128MB memory module for the time being and I got everything set up. And it posted! My Rage 128 works, my RAM of course works, the CPU from eBay works, the drives all work, and my motherboard repairs WORKED.
I picked up a case off of ebay, a lovely beige box with just a touch yellowed on the front, but generally it had a REALLY sturdy metal construction and lots of room for activities. I had to fab a new floppy bracket and add a HDD cage, due to the original combination cage being missing, but the rest of the case is so solid that it doesn't bother me in the slightest.
Of course, Windows 98 was the first choice of operating system, but a friend convinced me to try OpenBSD on it as well, so that lives on a secondary SD Card drive. Haiku unfortunately doesn't seem to want to boot here. I added a Creative SoundBlaster Live! and a Rosewill ATA/133 controller to allow me to use the full size of the hard drive, as the native BIOS seems to freeze when it tries to detect it unless you use the 32GB capacity limit jumper. I also picked up a Cherry mouse that supports PS/2 and I plugged a Focus FK2001 keyboard I have into it as well, cause it has lovely clicky ALPS clone switches and a native PS/2 interface.
I wanted to install more RAM, but the board doesn't seem to like the high density 256MB sticks I was using in Hela, so I ended up needing to buy some low-density 256MB PC100 DIMMs, and that solved the problem. 512MB it is!
Finally, I went ahead and bought a faster K6-2. I would have LOVED to get a K6-III or even a K6-2+ or mobile, but those are honestly INCREDIBLY expensive for what they are. A plain K6-2 can be had for like $15 or less pretty much regardless of speed. The one I ordered is a K6-2/533 but my motherboard doesn't support a 97MHz bus speed, so it's running at 550MHz on a 100MHz bus. A slight overclock.
So here's where we stand:
I'll have more GPUs soon courtesy of a friend from Spain sending over some parts, apparently retro PCs are much cheaper over there.