High-pitch noise from AC-Adapter

High-pitch noise from AC-Adapter

This appears in some AC adapters shipped with some T60, T60p, Z61m, T30 (they're possibly shipped with others, too) So far, Lenovo did not offer any feedback for this problem.

Mine (supplied with a T60p) made an unpleasant "crackling, whining" noise. My supplier (Hemini) accepted it as a warranty issue, and provided me with a new one; this new one is *totally* silent (even with my ear right up to the PSU). Good switched mode PSUs should be inaudible; noisy ones are either defective, (or very cheaply constructed). --RichardNeill 01:07, 3 May 2007 (CEST)