Miscellaneous laptop discussions : IBM Thinkpad A20M won't fully boot up

IBM Thinkpad A20M won't fully boot up

I've had this thinkpad since October 2000. It runs Windows 98 and until recently had no problems. The past few times I've tried to boot up, it goes immediately into the bios setup -- it doesn't seem to hold the date and time anymore. I have to reset it each time -- then the hard-drive seems to 'sleep' until I hit the enter key multiple times. Once I get it to boot, it works just fine. I'm wondering if there is a battery or something else on the system board that may need to be replaced? The main battery is fairly new and charges completely, so that is not the problem. I can't seem to find any info on this in the manual that I have access to online. Any help would be greatly appreciated.

Thanks.

Barbara L.