I just some new ones, they appear to have been made in 2010 (date stamp 1029A2) and I installed one into my 386 and everything seemed fine till I powered it on today and discovered all the CMOS settings are gone. Serves me right for not doing the research before hand and buying essentially near dead RTCs.
So my question is this, how can one test this thing to verify that it in fact the battery that is dead? Surely the thing would be supplying some sort of voltage to the motherboard for it to retain it's settings in BIOS? If so, on what pins?