I have a Macintosh II down in the basement that I had not touched for at least 3 years. I don't even remember where I got it or when... I figured it had a IIfx board replacement in it and that's why I kept it, but no... took a quick peek and there's a Mac II board in there.
The basement is usually hot & humid during summer, so I figured the soldered 3 volt batteries would be dead, or worse... exploded acid mess, and the board wouldn't start up.
Wrong! It started up and it knows the current date, and the time is about 27 minutes off.
Checked inside again and it is a near-original setup... one 800k drive (it reads disks!), 40mb Quantum 5.25" drive w/gold top (System 7 on it), no Motorola MMU (68551?) on the motherboard... just the Apple black chip, 8mb RAM.
Upgrades: there's what I think is a Apple 8-24 video card (the kind with all the VRAM soldered on board, no SIMM sockets) and an Asante ethernet card. Surprisingly clean... don't recall cleaning it up, but anyway...
This is pretty amazing, this thing has got to be near 25 years old now... with possibly the original Varta batteries... how could this be still working?