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MelbourneDellUs

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10 years ago

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January 15th, 2014 16:00

Latitude E7440 - Loud Processing Noises

Hello Community,

2 days ago I was given a new work laptop - the E7440 (its brand new).

Straight away I noticed some loud buzzing noises which a fellow colleague said was the fan. It's quite annoying. I soon noticed however when my laptop was idle these noises would stop, and when I clicked they would start again. Whenever I ask the Laptop to do anything these noises start up, and considering im active on the machine all day - they are giving me a headache.

There are high pitched, buzzing noises. And as mentioned are aligned to when the laptop is processing something. They also make sounds when I scroll the mouse for example.

Whats the issue here? My internal support team said deal with it. Is there an issue with the hardware though? Its brand new.

Cheers,

  • Klobeerder

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    Posted January 16th, 2014 08:00

    I have the same problem with my E7440 (also brand new). By searching on the internet I found out that it is probably the CPU and the noise is caused by 'Coil whining'. There seem to be more Dell laptops that have this problem:

    http://en.community.dell.com/support-forums/laptop/f/3518/p/19500507/20342666.aspx

    http://en.community.dell.com/support-forums/laptop/f/3518/t/19503698.aspx

    As I solution I tried in the BIOS to disable C states (lower power states of the CPU) and Speedstep but that didn't solve the problem.

    Another forum suggested to use a registry addin to prevent the CPU from going into a lower power state but I haven't tried it:

    http://support.microsoft.com/kb/975530/en-us

    If anyone knows how to solve this problem I would like to know...

    Very disappointing for such a high end laptop

     

     

  • 5059

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    Posted January 16th, 2014 13:00

    I noticed the noise went away/unnoticeable when I took out the power cord. So the laptop was running on battery only.

    Any ideas?

    I left my machine with out internal IT support team overnight and using my trusty old HP now. Will update you when I have some answers from them - although I will probably get the 'deal with it' response again. If that's the case I'm going to stick with my HP EliteBook 8440p - what a beast!

  • djiang816

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    Posted January 17th, 2014 08:00

    Hi,

    I just got my E7740 too.  Noticing the buzzing noise when the laptop is venting.  I think it might be the fan rubbing against the enclosure.  Please share if anybody finds solution.

  • Rusty1234

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    Posted March 16th, 2014 19:00

    I have had two noises from my Dell E7440.

    The first was a "fan hitting something" noise. It got worse/better when the case was flexed. I fixed this myself by removing the battery and the fan, and I noticed a magnet inside the discharge of the fan. Heaven knows what it is meant to do. I moved the magnet slightly so it wasn't hitting the fan blades and this solution has worked for me - no more noise.

    The second problem is a high pitched squealing noise emanating from the unit when a) operating on mains power and b) SSD (Samsung 256GB) is working as indicated by the hard disk light on the console. It's very distracting. I have read elsewhere that it may be related to the power supply. I assume that the CPU  and SSD revert to a lower speed (and power consumption) when on battery so that the noise isn't there, but when on mains power it's very noticeable.

  • vforget

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    Posted March 24th, 2014 08:00

    I also have similar issue. Can "resolve" it by doing one of the following:


    1. Work on battery, not AC.

    2. Put load on CPU, e.g. scroll document.

    3. Put laptop into high-performance mode, which I assume disables CPU throttling.


    I will definitely see if I this is covered under warranty.

  • vforget

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    Posted March 25th, 2014 11:00

    I also have similar issue. Can "resolve" it by doing one of the following:


    1. Work on battery, not AC.

    2. Put load on CPU, e.g. scroll document.

    3. Put laptop into high-performance mode, which I assume disables CPU throttling.


    I will definitely see if I this is covered under warranty.

    Update: Call to Dell tech support fixed issue with driver and BIOS update.

  • Rusty1234

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    Posted March 26th, 2014 20:00

    Great to hear there may be a solution. Can you identify what BIOS version you are currently using? And what driver did you update?

  • vforget

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    Posted March 27th, 2014 06:00

    Noise did return. I assume Call to Dell (via my IT department) likely put laptop through it paces so CPU was not in elevated C states.

    However, I did diagnose and resolve the issue on my own:

    Diagnose:

    1. Turn laptop off.

    2. Remove battery and bottom panel.

    3. Install battery. Leave laptop upside down.

    4. Open lid of laptop slightly, just enough to turn on and enter login password.

    5. With back panel off and laptop on I was able to isolate noise to below heat sink, suggesting it was CPU  whine.

    Resolution:

    1. Disable CPU C state in BIOS. Dell BIOS does not enable me to disable specific state, only all of them.

    2. Alternatively, I can disable specific states in Windows, but I do not want to modify registry just yet.


    Since resolving this, laptop does not emit whine/noise, and CPU fan does not turn on more that usual (practically never). I cannot comment on battery life post-C state disabling.


    I have another person in building who has same laptop and does not have coil whine, but does have cooling fan noise. So, as others here have pointed out, high pitched noise can be from multiple sources.

  • Revi L

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    Posted March 27th, 2014 18:00

    I have the same problem, brand new laptop and it is making a scratchy noise when it is processing or when I scroll the page. Updating BIOS with Dell tech support did not fix the problem.

  • BenConrad

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    Posted March 30th, 2014 07:00

    Confirmed that when removing the power the 'sratchy' cpu coil whine goes away.  I may try the C3 registry fix to see how that affects battery life.

    Ben