Laptop making weird squealing noise/monitor flickering
 

I have a Dell Inspiron 9400 laptop that I purchased in May 2007.

Lately, it has been making an odd squealing noise while running (very high pitched, sounds like when your ears are ringing), which is accompanied by the monitor occasionally flickering or going out altogether (comes back when I restart). The noise changes slightly depending on whether or not I am hooked up to AC power, and there is more flickering when not hooked up to AC. The noise is unbearable. Tried taking the battery out and re-inserting, also powering laptop down and shaking it around a little, no difference.

The only unusual circumstances involving this laptop is that it has occasionally been in my backpack in my car when the outside temps have been 40ish, which I didn't think was a problem but now I don't know.

Any thoughts/suggestions?

Re: Laptop making weird squealing noise/monitor flickering
 

Dieing fan? AC power effects it probably because your computer will go into a power saving mode when not plugged in which would reduce the amount of heat being spent which would make the fan turn less or is it a dieing monitor?,honestly don't know.
Probably still under warranty, check with dell and they will probably allow you to send it in to be fixed.

Re: Laptop making weird squealing noise/monitor flickering
 

Update: Noise is not noticeable when AC adapter not plugged in. Now, when AC adapter is plugged in, noise is very loud, extremely high-pitched, coming from the area where the adapter plugs into the computer, and after a few minutes monitor goes EXTREMELY dim - not totally black, but too dim to be seen without a flashlight - and the noise stops as soon as the monitor goes dim. Once this happens monitor is dim even after AC is unplugged and computer must be restarted.

Once computer is restarted and run solely on battery, the monitor flickers a little but is visible (dimmer than normal), and the high-pitched noise is no longer noticeable.

Re: Laptop making weird squealing noise/monitor flickering
 

I had the same problem with my Dell 5100, but I only heard a loud beeping noise once. The monitor started flickering like you described about 3 minutes after turning it on and starting up Windows. Then it wouldn't turn on. I wasn't under warranty anymore, though, so I bought a new computer. FWIW, I don't think it was the fan on mine. The computer wasn't on long enough to overheat.

Re: Laptop making weird squealing noise/monitor flickering
 

Might also be the backlight/inverter getting ready to go.

A lot of laptops will run the screen at reduced brightness when on battery power. There is a long fluorescent tube that provides the backlight.

I had to replace one not too long ago. Not because of squealing, it went dark.

Re: Laptop making weird squealing noise/monitor flickering
 

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Might also be the backlight/inverter getting ready to go.

A lot of laptops will run the screen at reduced brightness when on battery power. There is a long fluorescent tube that provides the backlight.

I had to replace one not too long ago. Not because of squealing, it went dark.

[/ QUOTE ]

At this point I really think it is the inverter.

The OP at this link describes my symptoms almost exactly: Link

Here is what I think is the correct part, for ~$40. Link

I am seriously considering ordering this part next day air and then either putting it in myself or having a friend do it. I do not want to wait 2-3 weeks to get my laptop back by sending it to Dell, even though it is still under warranty. They may actually replace more than needs to be replaced anyway.

Thoughts?

Re: Laptop making weird squealing noise/monitor flickering
 

Downside is you void you warranty by cracking the case. And you are out some $$.

Upside is it gets fixed faster.

My wife replaced hers by herself. It's not that hard.

Re: Laptop making weird squealing noise/monitor flickering
 

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Downside is you void you warranty by cracking the case. And you are out some $$.

Upside is it gets fixed faster.

My wife replaced hers by herself. It's not that hard.

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QFT, I hope you don't have multiple problems and fixing this one voids your warranty.

Re: Laptop making weird squealing noise/monitor flickering
 

Ack.

It COULD be the LCD display or something else, and the whole power issue may have caused other problems. I guess I might as well send it in just in case. It would blow hardcore if it was the bulb and I had voided my warranty - I'd be basically buying a new computer.

[censored] you dell

Re: Laptop making weird squealing noise/monitor flickering
 

[ QUOTE ]
Ack.

It COULD be the LCD display or something else, and the whole power issue may have caused other problems. I guess I might as well send it in just in case. It would blow hardcore if it was the bulb and I had voided my warranty - I'd be basically buying a new computer.

[censored] you dell

[/ QUOTE ]
I really recommend people get dell's accidental coverage warranty on laptops, it's really expensive $200-$300 but they will come to your home and fix your computer within a few days. If you drop you laptop and break lcd spill a can of coke in the keyboard all is covered by accidental warranty. Laptops are more difficult to work on than PCs and the parts are more expensive.