My motherboard is singing: this can't be a good thing

Last time my motherboard sang it was bad news. I used the HP diagnostic tests and it showed up nothing wrong. The only thing new is that sometimes icons disappear from the taskbar. I go into taskbar, uncheck something and check it, save it and all's well. But there must be a bug. The only new thing was to download Brink's shortcuts to the power profiles but Brink's stuff's always good stuff. I had a new video card put in about 6 months ago with a new power supply to go with it and my mechanic guy seems to know what he's doing. How much time do I have? What's the best course of action? I try not to overreact with computers. Thanks in advance.

None of the three, Sean. It is definitely a tune. A rather happy little tune. I don't recognize it. It happened last time I turned the machine on. I think it was off with the power switch off, which would rule out overheating. Thanks for your response. I'll open the case tomorrow when I have more time. Maybe it's dusty or something.

Thanks MeOnMine. I do have a high end video card because I use Photoshop and Lightroom to develop rather large photo files. The power supply was replaced with the card because my tech said without it, it would blow. So that sounds like a good idea to use the piece of tube to try to track it down.

But the sound hasn't recurred since turning it on. It would be hard to track it down if it doesn't sing :)

@linnemeyerhere: Thanks very much. I'll use the method of discovery above to see what it is.

Many thanks to you kind souls. What a great site this is!

linnemeyerhere said:

Sounds like a singing capacitor.

+1

Some well coat the caps with clear nail polish to change their tune.

Update: It started singing again. It took a week for it to happen again. I took the side off to look and I'm blowing the worst of the dust out. Then I noticed something odd. The fan on top of the new graphics card is still covered in its plastic. I'm not sure that looks right. But how to remove it safely is something I'm going to take my time to do. Can anyone advise on the right way to go about this please? I don't want to pull anything out of place. I'm very inexperienced.

What video card do you have? (You might want to update your system specs.)

On the box it reads Radeon HD 6750 but now I have a new problem. After dusting the machine with a photo blower and my mouth I turned it on and.... no picture. I'm using my other machine to type this. It's connected to a KMV switch but I unplugged that and tried it straight into the monitor. No picture!