[s0l1d]

I have a computer with Asus A7V333 mobo running WinXP SP1. I have this problem with the clock being changed after a cold start of the computer.

The computer's power is connected to a standard basic powerbar (nothing fancy like Monster's Powerbars) and I usually switch off the powerbar after I shut off the computer (so no power goes to the computer at all). I did some tests with how the computer was turned on and off, and even leaving it running over night. This is what I found:

a) If I leave computer running, the clock stays correct.

b) If I shutdown Windows (thus the computer also shuts down), but leave the powerbar ON, the clock stays correct.

c) If I shutdown Windows, turn off powerbar for 1 minute, switch on powerbar and computer on again, the clock stays correct.

d) If I shutdown computer, turn off powerbar, and sleep for the night or go to work for the day (usually for around 8 hrs, for work or sleep), when I come back to the computer, the clock gets changed.

When the d) senario happened, at first the clock had very radical changes (back to a different date in 1999, for example). But in more recent days, it is just several hours back from the actual time.

For example, last night I turned off the computer at around 1:00am late night and go to sleep. I shutdown Windows and turned off powerbar. I went to sleep, woke up, go to work, came home from work and I turned on computer around 7:40pm. I checked the computer's clock and it says 2:40pm. And this is shown in BIOS, not just in Windows. (this is a key point as it indicates that it is less likely, but not impossible, to be virus)

Can someone help me with my problem here? What could be the cause of the problem? Mobo? Clock battery, perhaps? If it is just the battery, then I can just get a replacement battery, right?

Solid

[Sampson]

Sounds very much like the internal battery. You will want to replace it since it is not holding a charge. Right now only your clock is affected but eventually many of the defaults in the BIOS will start to disappear.

[preiman]

I Agree. This is definitely your internal battery.