Is a high pitched noise normal?

So my laptop is about 13-14 months old. Its a Toshiba Satellite A300.
Now a few weeks ago there is a high pitched noise that comes from the laptop after i turn it on from sleep mode or just turn it on in general. the sound slowly fades away after a while and it seems that its louder if its on AC.
Is this normal? or is it something to be concerned of?

 

Nope, definately NOT normal! My roomies power brick did that, from keeping it plugged in too long. Got a new one and chucked the old one. But you say it happens even on batteries? I could be wrong, but it might be the PSU on the Mobo.

Any chance it's still under warranty? If not, is there a PC repair shop (or preferably one that specializes in lappys) nearby? I'd get that checked ASAP.

Good luck!

 

try changing the brightness of the screen.

It could be the inverter making the noise.
Changing screen brightness should change the pitch of the noise, so you can tell if that is the problem.

 

if it goes away when the cpu is under load, it could be the infamous cpu whine.

 

Yeah if it is CPU whine then it is normal! Noisy power bricks however are not

 

The pitch gets higher/lower depending on screen brightness.

 

yeah, I win

That means it's your inverter. I think it's normal. unless it's a new problem?

 

The inverter should definitely not be hissing. It might be a sign that it's either starting to show it's age or there is a loose connection somewhere around the lcd circuitry. The only time my lcd made noises was when one of the backlight cable got frayed and the insulation became damaged.

 

I dont think you can describe it as hissing.

My notebook does it (not very loud though). Check all of your LCD screens, I'm sure you will hear it.