Does your machine make noises during recharging?

[teetee]

Machine: TP X41 Tablet
Battery: extended battery from IBM(SANYO cell)

The source of the noise is not from hard drive, fan, or speaker. It sounds like loud static (I hate to image it's the sound of burning capacitor, but it could be). It only happens for a few minutes right after I plug the AC power in with the battery is attached. If I remove the battery then the sound goes away.

I am just wondering if there is any concern for this type of thing from anyone. I guess it probably is not a big deal since the machine works fine whether if the noise is there or not.

[phool@round]

Possible loose connection between the system board blades and battery clamps. Sizzling is still not a good thing to hear, it's arcing. Check the batteries clamps for spring tension. If they're good then you might have a component coming loose on the system board, possibly an inductor or coil which will be near the battery.

[j-dawg]

Is it a sort of high-pitched squeal coming from around the power LEDs?

If that's what you're hearing, I get that too, but I just ignore it. It's quiet enough not to be a big deal for me.

[rek]

It's most likely inductor noise from the power circuitry, which is nothing to be worried about. (Kind of like how mains power transformers mounted up on telegraph poles make a buzzing noise, but at a much smaller scale)

Useless fact: on most Core Duo notebooks, if you put your ear up to the laptop, you can "hear" the CPU change power state by the tone of the inductor buzz