Is this a CMOS Battery Issue?

[Stoney]

My second rig is an old Pentium 3 1.2 GHz Tualatian cpu on an ASUS TUSL-C2 motherboard with an Intel 815E chipset. I have the maxium RAM I can run: 512 megs of PC 133. OS: Windows XP. It has been rock solid, never giving me a problem until now.

When I turned it on this morning I could not access the internet so I checked for lose connections on the router, modem, and PC. They were solid. As I moved my PC gently to check the connections, though it did lean slightly to the side, I thought I heard the one harddrive (2 WD 80 gigs in a master-slave configuration) start again -- but I am not 100% sure. One thing I am sure is that my mouse would not work (arrow froze) after I heard this start-up noise and I had to reboot.

To make a long story short when I restarted it would not boot beyond the IRC screen. In fact, the IRC screen showed no Primary Master Harddrive, only the Slave drive. So, I went into the BIOS and though all drives were on AUTO setting the Primary HD was not recognized in the submenu but the Slave was. I entered the Default Settings. Nothing. I did it again. Nothing.

So I turned it off. Checked all connections within the PC and were all solid -- nothing lose at all. Turned it on and, bingo, Windows loaded up fine. I could access the internet as well (I'm typing this from the computer I speak of).

I have heard that when the CMOS battery begins to fail all kinds of issues begin to happen. It hasn't been changed since I built this which was 5 (6?) years ago. The thing is I am not sure what is lost when changing these batteries out. What will I need to do once I change it out? Will the BIOS revert back to the one that came with the motherboard? I have the latest which dates back to 2002. Is there a way to save this latest BIOS?

Lately when I've had to go into the BIOS and save it would fail to take the changes without freezing at the IRC screen. In fact, even if I didn't make changes it would freeze. I'd have to turn it off and the next day everything would load.

Note: Ran WD diagnostics and both drives passed without exception.

[saphalline]

This sounds like it could possibly be more than just a dying battery, but the cheapest & easiest thing to check right now would be the battery. Try replacing it and see what happens.

No, the battery isn't for the BIOS itself, it's for the CMOS, which stores the BIOS settings that you've changed. The BIOS code itself is stored on an EEPROM chip and is totally safe unless you "flash" it. The BIOS version will stay put when you remove the battery, but you will have to go through the menus and re-do any changes.

[mjc]

It also stores all those variable things, like which CPU s in the thing, not just the actual changes you made.

Sometimes when the battery starts to go, the only sympyom will be a funny acting clock as the time is reset every power cycle. Other times, there is a bit of voltage left and some of the settings don't revert to the factory defaults...but generally this results in no-boots that are accompanied by all sorts of strange sounding errors or warnings of changed parameters.

This, on the other hand sounds more like a hard drive problem. Or more specifically a controller problem.

I would examine the motherboard closely for any bulging or leaking capacitors.

This could be step two after swapping out the battery...just in case it is truly just a settings problem.

[Stoney]

mjc, strange you should mention the caps because I did check them before I read your post and the caps show absolutely no bulging or leaking. They look very clean and very solid.

And as I said the WD harddrive diagnostics shows the Primary and Slave showing no errors or issues. If it is a controller problem how do I determine this and what do I do to correct it? I really would like this to run strong and well as long as I can. My family needs two computers!

[mjc]

Try swapping the hard drives and the optical drives...usually the HDs are on the Primary IDE channel and the opticals are on the Secondary. Change the cables at the motherboard side. This shouldn't change any Windows settings, but if it is a controller issue then you should lose your Master optical drive (or if there is only one, you should lose it). If it is a drive/cable/BIOS issue the problem should follow the switched drive...

[saphalline]

Or since you say your family has two computers, test the hard drives on the other computer. But again, it won't hurt to replace the battery.

[Whyzman]

So I turned it off. Checked all connections within the PC and were all solid -- nothing lose at all. Turned it on and, bingo, Windows loaded up fine."Nothing loose at all" Yet, after you messed with the connections all is well... I would suspect that just moving the connections around as you were testing them must have reseated something...or, just a coincidence? Maybe, maybe not! ;)