Time sucks

Have trouble keeping right time. Replaced battery 8 times. Bios ( TIME ) won't stay, most of the time it won't do auto sync from desk top. DAY and DATE stay correct. ONLY time keeps messing up. XP-Pro 64bit.... Gigabyte MA785G-US2H.......wudup ?

ignore the " FIC"....... had to chose something or it wouldn't post.
pulled the new battery and walked away for a while. came back in ( forgetting about battery ) started machine and did my stuff. ran fine after setting stuff up again. realized I left out battery. shut down, put battery back in, restarted. been stable since. go figure...... one for the record books......... thanks for suggestions.