LCD whine

[meeotch]

I've just noticed that the LCD on my T42p produces a buzz/whine when set to anything less than 100% brightness. It almost sounds like a mechanical noise, such as would be produced by a fan that was rubbing up against something.

It is not, however, fan noise. It goes away when I hit Fn-F3 to turn off the LCD. It also seems to respond to pressure on the lower-right corner of the screen, and is quieter at some brightness settings ("4 bars" is quieter).

At 100% brightness, the noise stops altogether. However, since the max brightness when running on battery is set to less than 100%, it's noisy all the time when not on AC power.

Has anyone else experienced this?

[rkawakami]

If you plug in "lcd AND whine" into the Search link at the top of the page, you will find 14 hits. Some of them discuss this issue.

[meeotch]

Yup - sounds like it might be a "singing" inverter, given the behavior I described above. Don't know how I missed that in my previous search.

I suppose that it just started singing recently because it's getting old. (Although I did have the backlight replaced about six months ago. I don't know if they did the inverter at the same time or not.)

I suppose at < $30 on eBay, it's worth trying to swap the thing out myself. I even googled up a guide (specific to the T41): http://www.laptoprepair101.com/laptop/2 ... backlight/

[roberts5]

Are you using an IBM or 3rd party power supply. This happens to me w/ the 3rd party supply, but not IBM. The 3rd party supply has a 3 prong adapter, while the IBM is 2. might be related to that.

[meeotch]

Are you using an IBM or 3rd party power supply.

All stock power (batteries & power adapter).