more and more often my Thinkpad R61i (8918-DDG) does this famous high pitched sound when on Battery.
I found some hints around serveral forums but some solutions are only for Linux (kernel-options..) others tell me to disable CPU-Power-Management in the BIOS. But since the fan is far too noisy (another lenovo-Disappointment) and the standard battery far too weak this is not an option.
should i really call Lenovo-Service to replace it? (as some souces suggest..)
(to be honest: i am pretty disappointed about my Thinkpad.. for years i dreamt of my own thinkpad and now its a heavy, creaking, noisy-fan, buggy-driver plagued piece of computer... maybe i should have stuck with HP...)