Thinkpads Forum

Hey guys,

I just got a new thinkpad x61t a couple days ago and I'm beginning to notice a very annoying buzzing noise coming from the laptop while running off the battery. It varies in volume and ranges from the barely audible to audible. I've researched this a lot on the forums/web and I've come across a variety of explanations ranging from the Core 2 Duo processor reclocking itself hundreds of times per second to USB power messing with the motherboard.

Anyways, I'm wondering if anybody else has this problem? If the room is silent, I can hear the buzzing and if I put my ear to the keyboard then i can DEFINITELY hear it. It sounds like an electrical buzzing of sorts.

Is it the screen's backlight inverter?

ken830 wrote:Is it the screen's backlight inverter?

Hmm... I have no idea and I don't know how to test that?

Anyways, as an update to the story, I called Lenovo technical support and they said that it is a problem that does crop up every once in a while on their laptops. The problem is (this is a new one), when on battery mode, the battery tries to recharge itself sometimes when it shouldn't be. It's a problem with the motherboard apparently.

They said that I need to send it in for repair so a box will be here on Friday and I'll get it back in 3-5 business days so they say. Anyways, hopefully they'll fix my problem. I"ll be sad to be missing my new thinkpad though

You should try turning off the screen to see if the sound goes away...

I know most notebooks are configured so that the screen dims in battery mode to conserve power. The CCFL backlight is powered by an inverter to convert DC to AC. Many designs control the brightness using PWM. At certain frequencies, you may hear it whine/buzz...

If that is the culprit, it may just be that way with all of the units, or yours just may be just a peculiarity...

This problem has been existent ever since I got my X60 in March 2006.

I'm not surprised that the problem has persisted to the new X61t generation.

I'm not surprised if it has been existent before the X60's series.

Apparently, there is no (useful) workaround for it.

http://www.thinkwiki.org/wiki/Problem_w ... tch_noises

PS: If you try to have disk activity while on battery (e.g., defragment the disk, open a .doc .pdf etc), the buzzing sound seems to go away. But once the laptop goes back to an idle disk state, the buzzing resumes. Try it.

I had the problem with my X24... so yes, seems like a problem that will never go away. I also have it today on a new Asus laptop. They noise are related to (in my cases) the CPU. When the CPU goes into deeper idle states (C3-C4) the noise comes. Very annoying for those with healthy ears, and quiet surroundings.

Alright, an update to the story.

I got my X61 back from the repair centers and in their description they said:

Bios/Embedded Controller updates prescribed on IBM support page were performed on your machine to ensure reliability and performance efficiency.

So it looks like they updated the BIOS but that doesn't make much sense because there's only one BIOS available for the X61t on the Lenovo webpage.

Now, when I turned on the laptop, guess what! THE BUZZING SOUND IS STILL THERE!!! I didn't expect much because they didn't replace any parts and applied a meaningless BIOS update.

They did include another piece of paper that says that while testing at the depot, they determined that my battery needed to be replaced. So, I called them up and they're sending me a replacement battery tomorrow so I'll see if this new battery helps.

If not, then I'll just have to get used to the buzzing, bleh

Sigh ... it looks like Intel / Lenovo still haven't fixed the same buzzing found in X60s. I bet if you stop the cpu from going into C3/C4 sleep states the buzz will go away.

n00b_thinkpad wrote:Alright, an update to the story.

I got my X61 back from the repair centers and in their description they said:

Bios/Embedded Controller updates prescribed on IBM support page were performed on your machine to ensure reliability and performance efficiency.

So it looks like they updated the BIOS but that doesn't make much sense because there's only one BIOS available for the X61t on the Lenovo webpage.

Now, when I turned on the laptop, guess what! THE BUZZING SOUND IS STILL THERE!!! I didn't expect much because they didn't replace any parts and applied a meaningless BIOS update.

They did include another piece of paper that says that while testing at the depot, they determined that my battery needed to be replaced. So, I called them up and they're sending me a replacement battery tomorrow so I'll see if this new battery helps.

If not, then I'll just have to get used to the buzzing, bleh

Well, another update. Got a new battery and new AC Adapter and the buzzing is STILL THERE.

I took a look at some of the sites you guys posted and did a bit of research on my own and I discovered that if I go into the USB Root Hub properties in Device Manager and go to the Power Management tab and uncheck the box that says something like "Allow the computer turn off this device to save power" then the buzzing goes down dramatically! ( I have to do this for every USB Root Hub btw).

However, the only downside to this is that my battery life decreases by at least 40 minutes which really does suck.

Anyways, I'm just going to live with the noise because I would like 40 minutes of battery life. Most of the time I can tune it out but sometimes it gets unbearably loud. I hope that this problem will go away with more use of the machine. *Fingers crossed*

IBM/Lenovo always updates your BIOS when you send your machine in - regardless. I sent the same machine in 3 times (back to back to back) and every receipt said that they applied a BIOS update. It's meaningless. They basically did nothing to your machine.

I'd like to add, that my comp only buzzes when the battery is low on juice. Right now it's at 97% and no buzz.

I'm gonna try updating the BIOS and see if that does anything.

x61t btw