I work nights in a care home. We have a rather old PC that is being problematic. I booted it up a couple of weeks back when I was on night duty, and at POST, the screen read that the CMOS settings were incorrect. I went into BIOS and reset the date and time, rebooted, and the PC successfully booted into XP! Problem solved I thought. However, on booting the machine a few days later, the CMOS settings had been lost again - so I reset them and all's well again. Anyway, long story short, the CMOS setting don't seem to hold once set. I'm thinking that the battery is screwed and needs replacing - any other thoughts? Cheers, David.
I would first replace the battery, there is a good chance that your battery is dead, or close to it - If it is an older computer as you said, that would be the best thing that could be wrong with it.