So. They say there are several impulse transformers, all of them placed on the mainboard, including the area close to CDC (where the LCD cable is). These ones work with the TFT backlit lamp and are (or become in a short time) often that noisy. It is caused by a bad filling of the transformers with a...

Ambassador, as soon as I'm not sure about the placement of the converter, I've forwarded your question to my friend from IBM service. I've got a new t43 (2668-84G) this week and have just the same problem. The noise comes somewhere near from Access IBM button. Awaiting for the answer from IBM.

Just for information: according to our local IBM services (Moscow, Russia) the mentioned noise is a known problem of T4x/T4xp series (the noise comes from the low-to-high voltage converter of the backlit LCD lamp) and it is covered by IBM guaranty, therefore the converter is exchanged for free. That...