Yep should be just one battery and it keeps the CMOS memory alive. Remove it and you should loose the clock timing. Most PC's will recognizes this as a problem and prompt you to set the clock when you boot up. I never saw one that would keep time when the battery was removed.
Minuteman10
I forgot this go to a computer supply store and purchase a power supply tester. They can be picked up for $10 or less most times. Follow the instructions and test the power supply. Most likely not the problems but worth a shot.
Do as you already did but remove everything by that I mean all memory, PCI cards, Keyboard monitor and mouse. (leave the CPU in) then power up to see if you get error beep codes if you don't scrape it.
Sadly it sounds like time for a complete over haul or install used hardware unless you can find that motherboard new.
My advise is if you get a new pc put that hard drive in as a slave. It does not sound like you should have lost any data. It should still make good storage media.
Minuteman10
I forgot this go to a computer supply store and purchase a power supply tester. They can be picked up for $10 or less most times. Follow the instructions and test the power supply. Most likely not the problems but worth a shot.
Do as you already did but remove everything by that I mean all memory, PCI cards, Keyboard monitor and mouse. (leave the CPU in) then power up to see if you get error beep codes if you don't scrape it.
Sadly it sounds like time for a complete over haul or install used hardware unless you can find that motherboard new.
My advise is if you get a new pc put that hard drive in as a slave. It does not sound like you should have lost any data. It should still make good storage media.