Currently tring to get some stored old PCs runnig again.
My 286 has the combined battery/RTC devices that are dead now. It refuses to boot with a mesage that it lost its BIOS settings.
Seems impossible to preserve those for the future as those devices are not produced any more.
A 386 is still working perfectly, but the battery is already leaking.
The Pentium 100 that I used for about 10 years seems completely dead. :-(
Maybe the Pentium II is old enough to use all the SW on this site.
Otherwise I'll have to find some replacements. I hope there are still enough (used) spare parts in working condition from that time available.