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Ze0nite
12-26-2013, 11:41 AM
When everything's completely silent I can sometimes hear a buzzing sound coming from the leftmost side of the computer, since the hard drives aren't there I'm suspecting it's either video or cpu. I don't think it's the fan since I can hear it power up and down with it's characteristic sound but the buzzing is the same and is not related to the powering up or down of the fan, it's a very dim buzzing that turns on and off but for it to happen there's also an even fainter hum coming out. I literally have to put my ear against the computer to hear this hum but the buzzing is kinda audible when everything's silent. Any form of audio will cover it up so it's not as loud as some might imagine but it bothers me.

I heard some video cards do some sort of sound under stress but I hear this when I'm doing literally nothing but browsing the web. I wouldn't care if the sound isn't some sort of malfunction and I don't want to go throught the trouble of sending it to Asus for repair to find out since that would leave me without a computer for a month so I'd rather not do it unless it's absolutely sure it's some sort of malfunction.

hmscott
12-26-2013, 11:57 AM
When everything's completely silent I can sometimes hear a buzzing sound coming from the leftmost side of the computer, since the hard drives aren't there I'm suspecting it's either video or cpu. I don't think it's the fan since I can hear it power up and down with it's characteristic sound but the buzzing is the same and is not related to the powering up or down of the fan, it's a very dim buzzing that turns on and off but for it to happen there's also an even fainter hum coming out. I literally have to put my ear against the computer to hear this hum but the buzzing is kinda audible when everything's silent. Any form of audio will cover it up so it's not as loud as some might imagine but it bothers me.

I heard some video cards do some sort of sound under stress but I hear this when I'm doing literally nothing but browsing the web. I wouldn't care if the sound isn't some sort of malfunction and I don't want to go throught the trouble of sending it to Asus for repair to find out since that would leave me without a computer for a month so I'd rather not do it unless it's absolutely sure it's some sort of malfunction.

Did you rule out the audio system by switching the output to something like "Realtek Digital Output"? It could be audio leakage / noise - switching to an unused output from speakers will remove that as a possibility.

If it was the right side I would have suspected the charging circuit. You could remove that as a possibility by removing the power cord while you hear the buzzing.

Another possibility is that it is a fan on the verge of starting up, vibrating on the spindle. Rare, but I have seen it.

If you have a spinning HD, it could be a vibration conduction.

You could pull the back panel and run the laptop upside down to track down the source. A stethoscope can help track the noise to the source too.

Kinda hard to debug without hearing the noise in person, but with these suggestions I think you can be creative and trace it to the source.

I don't hear anything from the G750JH when the HD spins down and the fans are stopped.

Ze0nite
01-04-2014, 09:39 PM
I did rule out anything related to the power sources, according to the ventilation diagram of the G750, the thing making noise is either the CPU or the CPU fan but I think it's quite a weird sound that doesn't appear mechanical to me.

The sound isn't at all coming from the HDD, that thing makes a sound of it's own.

This sound isn't always on, it's quite rare actually. Heard it 3 times before but it won't stop until I shut down the computer.

I am VERY sensitive to sounds, so there's that.

hmscott
01-04-2014, 11:33 PM
I did rule out anything related to the power sources, according to the ventilation diagram of the G750, the thing making noise is either the CPU or the CPU fan but I think it's quite a weird sound that doesn't appear mechanical to me.

The sound isn't at all coming from the HDD, that thing makes a sound of it's own.

This sound isn't always on, it's quite rare actually. Heard it 3 times before but it won't stop until I shut down the computer.

I am VERY sensitive to sounds, so there's that.

Ze0nite, does it correlate with the fans running? If it is still making the noise after the fan stops, then it might not be the fans. When a fan is making startup noise that noise stops when it is running, and stays quiet when it stops.

I usually wear headphones, so my laptop could be putting out soft rap music and I wouldn't know it ;)

Assuming this is normal, you need to either figure out a way to mitigate the effect, or return it - if you are within the return period - because trying to RMA something this subtle will be problematic...

How far away from the laptop can you hear it, without straining, it might work for you to push it further out, and set the laptop on sound deadening material. I leave on the White sheet that came between the keyboard / screen to protect the screen from key impressions / dirt and that might be enough to keep the noise in without stopping air flow. This works for me because I use an external keyboard / pointing device.

During the times I have been sensitive to small sounds, like those that keep me awake, I have used a fan or while/pink noise generator to push those noises below the sound floor. Music, Video, etc - some background noise to cover up those small noises that come through during times of mostly silence.

I find that keeping things too quiet exaggerates the effects of small sounds - we are all susceptible to relative changes in sound.

Let us know what you end up getting to work for you :)