System Time Problem

I've come here to find answers to many problems over the years and this one has me stumped and I can't seem to find a solution even after days of searching (never failed to this point.)

I have a P4 2.0Ghz computer that is mostly a bunch of parts I had lying around but centers on a Compaq board that was "rescued" from a box of parts. I'm pretty sure the processor came with the board but everything else is non stock (meaning isn't original equipment).

The problem I'm having is that the CMOS doesn't seem to want to keep track of the time. By example I noticed the time was wrong after freshly installing Windows XP Pro onto the machine even after adjusting the time in the BIOS before starting the install. The time was 3:10pm. I manually adjusted the time continued with the installation of drivers and programs and such until I had to restart. Upon restarting the time went back to 3:10pm despite it being after 4 now. Odd. I adjusted the time by syncing it with the time servers over the internet and didn't think much of it until had to restart again. This time back to 4:17pm (which is the time the internet servers adjusted it to).

It appears the time is returning to the value that last entered into the computer and not keeping track of it when it shuts down.

It was a fresh instal of XP and there aren't any errors or conflicts that I haven't already resolved.

I have bought and installed a brand new CMOS battery.

Windows Time Service is ON, active and set to automatic on startup.

I flashed the BIOS from version 2.14 to 3.18.

All to no effect. The computer runs perfectly except for this time problem. Any ideas would be greatly appreciated.