What changed my BIOS's configuration settings?

[Sylvander]

I noticed as my PC booted that the "DirectCD" icon in the System Tray had a red X through it, which is an indication to me that there has been a failure to detect and enable my CD-RW during the BIOS POST.

So I studied the drive during startup and noticed that the LED was glowing constant/unblinkingly green.
When all's well the LED blinks as the BIOS communicates with it.
I did nothing to it, but just kept an eye on what was happening.
Then I noticed the LED glowing RED.
Didn't like that so I took a look during Startup at the BIOS detection info behind the splash screen and, sure enough, the drive wasn't being detected.
So I went into the BIOS Setup to take a look to see whether the drive was listed correctly.
But it was listed as "None".
So I reset it to "Auto", and then "Save & Exit Setup", and on Restart the drive was detected and displayed by the BIOS POST, and once into Windows all was well, with "DirectCD" not disabled.

So how come my settings had changed?

Any ideas?

I don't think a virus has done this; no hints of any infection.

[mjc]

1. Stray tachyon from the Mutara nebula interferring with interferring with the electron transfer in the CMOS module...

2. Failing CMOS battery.

3. IDE connector is working itself loose.

4. Failing drive.

5. Failing IDE controller.

6. IDE cable failing.

7. Unstable voltage on one of the rails of the PSU (probably 12v).

(My money is on the tachyon...;))

[Sylvander]

Nice list. :D

Failing CMOS battery seems somehow to be rising to the top of my mental list of culprits, but I'm trying to keep an open mind.
You know...
The kind that the wind blows through and makes a gentle whistling sound. :)

A couple of months back I was having problems of this nature with this drive.
At that time I thought it was the IDE cable coming loose or not connecting well.
So I kept unplugging and replugging it, which seemed to do the trick.

More recently strange things were happening very infrequently, although the drives worked ok and both showed up in Windows Device Manager as working ok.
The CD-ROM [Secondary Master] was the only drive of the two being detected and displayed by the POST.
Yet it was the CD-RW [Primary Master] that showed a blinking green LED, whilst the CD-ROM showed unblinking green [or is it yellow?].
I just left well alone since they both worked just fine.
Now both drives are being detected and displayed, or they were the last time I looked; I wouldn't bet that they keep that up.

I'll keep checking at each Startup if I can remember.

[Sylvander]

Yep, both drives are being auto-detected, and the results of that detection is displayed on-screen by the POST, and it's correct.

So it's working better than it did before. :D