Eliminating the CPU "hiss" (whine?) from the T61?

[Hellbore]

Originally Posted by Grimhound

Why the heck do they even sell laptops with the Core 2 Duo architecture if Intel can't fix their own chips to work right?

Huh? They do work right, they just sometimes make a noise. It's not that loud even. Besides, the noise doesn't even come from the CPU it comes from the motherboard.

[mscholtz]

I think I may have this problem, but not sure it's the same thing.

My symptoms are:
* a hiss/hum that seems to be coming from the right side of the machine (sounds like white noise, or a much quieter version of a modem after the handshake)
* pretty constant, although sometimes I'll hear changes in pitch or sudden shifts in the sound, or very quiet "beats". not only during HD reads/writes
* happens whether or not on battery - can't detect any different battery vs. AC power
* tried the recommending settings in RMClock, and no noticeable difference (should just have to click Apply after changing the settings to hear the difference, yes?)
* tried disabling "USB Selective Susupend" in power mgmt, no dice

It's not that bad a noise, but it's definitely the loudest thing about the machine, louder than the fan (at low spin) or what I think is the HD (although I can hear HD reads/writes behind this other noise).

I suppose it's possible I got a loud HD and I'm just hearing the HD spin? I guess I could test that by removing it and booting up.

Any further suggestions are appreciated.

[michelkenny]

Originally Posted by mscholtz

I think I may have this problem, but not sure it's the same thing.

My symptoms are:
* a hiss/hum that seems to be coming from the right side of the machine (sounds like white noise, or a much quieter version of a modem after the handshake)
* pretty constant, although sometimes I'll hear changes in pitch or sudden shifts in the sound, or very quiet "beats". not only during HD reads/writes
* happens whether or not on battery - can't detect any different battery vs. AC power
* tried the recommending settings in RMClock, and no noticeable difference (should just have to click Apply after changing the settings to hear the difference, yes?)
* tried disabling "USB Selective Susupend" in power mgmt, no dice

It's not that bad a noise, but it's definitely the loudest thing about the machine, louder than the fan (at low spin) or what I think is the HD (although I can hear HD reads/writes behind this other noise).

I suppose it's possible I got a loud HD and I'm just hearing the HD spin? I guess I could test that by removing it and booting up.

Any further suggestions are appreciated.

On the T61's the whine that we're talking about comes from the CPU, which is on the top left side of the laptop. Your noise could very well be the HD spinning since that is underneath the fingerprint reader (lower right side). Our noise is also only on battery power.

[Bashar]

does any of the solutions here works for T42P ? mine started to give the same sound from the fan on the side too!

[paulmt123]

My inspiron 1520 is definitely affected. I think part of the problem is the rest of the laptop runs so quietly this whistling high frequency noise is audible.

My previous inspiron 1520 was not affected so it may only be some. I took that back due to hard drive racket (it made a grinding noise that didn't sound healthy and PC world agreed and replaced it). Interestingly enough this one has a different make of hard drive which runs very quietly but it suffers from this CPU whine.

Its a very strange sound this. Reminds me of a ZX spectrum loading from a tape!

Its not particularly loud but like others say its a bit like an annoying clock, once you hear it you get fixated on it! Intitially I thought it was interference playing through the speakers. But when I searched for inspiron whistling sound I found exactly what it was.
Infact it can even be heard over moderately loud music!

The fix is to disable C4 mode in a program called RMclock.
This virtually eliminates the sound. I say virtually because it can still be heard when you scroll up and down with a mouse and put your ear to the base of the PC and its still there, only quieter. This is perfectly acceptable though, not really annoying. The noise with C4 enabled most certainly isn't. So disable it. Does run warmer, fan cuts in every now and then but that noise isn't of a frequency to be irritating even though its far louder.

If you can still hear it, and I can imagine some can then download l8kfangui and set fan speed to minimum. The quietly running fan at minimum speed will drown it out and the laptop will run cooler too! This fix does increase temperatures but only into safe ranges. Far lower than in a game for example

[amstel78]

I have the same hiss - not really bothering though. Usually the noise goes away after the laptop finishes booting into Vista. Makes no difference if I'm on AC or battery.

[vkeks]

Originally Posted by LMN8R

I just wanted to follow up here:

-Checking the "Disable C4 mode" fixed the problem, but caused hard freezes in my computer multiple times over only a day or two.

-Un-checking "Enable Popup mode" also fixed the problem, and I'm running on a week or so, so far, without a single crash.


Also, un-checking "enable popup mode" doesn't seem to hurt battery life nearly as badly as disabling C4 mode.

Checking "Disable C4 mode" caused the noise to go away, though a crash soon followed in less than a minute.

Un-checking either "Enable popdown mode" or "Enable popup mode" doesn't seem to do a thing.

R61
XP Pro
T8100 - 2.1Ghz

[DennisW]

I had the same problem but it went away when i installed the power manager software.

Running a clean install of vista business x64 SP1.

[rbilling]

I have the same problem. From what I've heard it is due to a component on the motherboard (probably an inductor) near the CPU resonating when the CPU changes power states.

If you plug in a USB device to any USB port it stops apparently; it does for me at least. Using this RMClock utility like others have said also solves the problem. A permanent fix is to disable CPU power management in the BIOS, although this will negatively affect battery life.

I don't see why we should have to run third party software or cut battery life to have a system that isn't making annoying buzzing sounds, but it happens with every manufacturer and no one has bothered to make the vendors aware that it's a problem, so that's just the way it's going to stay I suppose.

[Archer36]

I sent mine in, they upgraded the bios and shipped it back... something I could have easily done. I don't event think they read my note that it only happens on battery. On the phone with them once again

Edit, its going back once again, but to a higher level department.