T61 electric "buzz" sound

Hi All,

A few days ago I've discovered that when I use my T61 on battery, I hear a a faint electric "buzz" sound that is most noticebly on the lower right corner of the laptop (put your ear just next the CD/DVD drive to hear it). The sound is most noticeable when you use the laptop in a quiet room, and is quite irritating.
I've checked this issue with my friends T61P and he doesn't have this problem, so I guess it only appears on some machines.
I've searched this forum for similar complaints without any findings. While searching the net I've found similar complaint from someone with T61, and he claimed that the CPU is causing this noise when it is switching into low power state (on battery). I've plugged my laptop to the wall socket, and indeed the noise stopped. The person on the NET mentioned that he was able to solve his problem by changing a setting in his O.S -Linux- to prevent the CPU from going into low power state.

I went to Lenovo service center and they affirmed that I'm not the first one with this problem -they also said that it is probably related to the CPU- and that they are waiting for an answer from IBM/Lenovo center.
They said that they can either replace my motherboard or I should wait for an official answer from IBM center. I've mentioned the solution I've found on the web, but they replied that it doesn't solve the problem. I've decided to wait for an official answer as maybe there is some easy solution instead of opening my new laptop.

Does anyone else here suffers from the same problem?

 

I began to notice this same issue a few days ago. It's very irritating when working in a quiet classroom or library setting, and it is hardly a new issue - some T60s had the same issue, and the MacBook Pro's first few generations were notoriously plagued with it. It's an issue with the speedstepping on the new Intel processors. Sadly I don't know how to fix it, as none of the BIOS settings I tried made it go away; but plug the system in and voila - silence. I would have hoped Intel would have remedied this issue for their latest-and-greated generation of hardware, but obviously they have not. I suppose expecting Intel to address major issues in a timely fashion is expecting a bit much - my WEI memory score for my 4GB of DDR2-667 is 4.8 on my laptop and 5.9 on my desktop because Intel still uses the archaic FSB method, and look how long we had to put up with Netburst lol.

 

What surprises me the most is that if indeed it is a CPU issue, then it should appear on all laptops, but as I mentioned the noise doesn't appear on my friend's T61P. My guess is that it is a combination of CPU and board.

 

what's the processor in yours and what's the one in your friend's ?

 

http://forum.notebookreview.com/showthread.php?t=154034

http://forum.notebookreview.com/showthread.php?t=146261

 

My apologies. Apparently this subject was discussed, and I didn't find it.
Anyway, I've tried the suggestions that appeared on the mentioned threads and it didn't help. I'll wait for Lenovo reply on the matter.

 

any updates? my computer has the same problem!

 

My t61 has the same problem.
I've changed the config of the sound card (changing 16bit to 24bit, and back to 16 bit), but the problem still here. it seems to be the battery does not have enough power the drive the speaker.

And I found another problem, that is the heatsink in my notebook is aluminium, not copper. This website compared both r61 and t61. http://www.tpuser.idv.tw/articles/santarosa-test-2.html

 

its the cpu and motherboard. Laptop motherboards use cheap caps and when the cpu changes states the electric noise is coming from the caps BTW my Santa Rosa HP 8510w does not have this issue.