Silent on battery but noisy on AC - swift 3

CARLTONBP
CARLTONBP Member Posts: 14

Tinkerer
edited November 2023 in 2019 Archives
This is puzzling me. There's a fan like noise on ac but the fan isn't running and the HDD isn't running either. It's not really loud but it's there, I guess just general laptop hum. But unplug the laptop and it goes really silent. It's fantastic. I've checked power options and gone through all advanced settings, only difference is 10% screen brightness. Temperature is the same, it's currently 39 on battery, which is usually where it is on ac. Any ideas as to why the difference.
SF315-52 with 512gb SSD and mechanical 1tb.

Thanks

Best Answer

  • CARLTONBP
    CARLTONBP Member Posts: 14

    Tinkerer
    Answer ✓
    Found the solution - it was on an older thread you posted on, except I'm doing the opposite.
    I bought a non-grounded power supply. Took ages, had to check for safety, find a reputable safe one. Turns out I didn't need it but at least I have one.

    Using HDDscan I worked out the HDD wasn't spinning down even though it sounded like the spindle was resting.
    W10, progs etc are on a 512gb ssd which is in the old optane port. I still have the 1tb hdd (toshiba) that came with the laptop on which are a few files but no progs.

    His problem is the opposite of mine, he's using the HDD as his main drive and for him it was constantly spinning up and down which I know is very annoying as I had HDpharm on an old laptop to stop this.

    What I did
    1. I enabled all the advanced power settings that Acer restricted access to, (not impressed Acer) 13th post down. Not sure if that has changed anything but it's nice to have access.

    2. THen 9th post down I added "EnableAPM"=dword:00000000 to the registry.
    I guess it's a legacy setting from the optane and HDD being main drive.
    The HDD now rests after 25seconds.

    Possible alternative
    I had a look at Intel Rapid storage app. I noticed under performance, there is now enable/disable link power management ( don't think it was there before). So I think this can now be controlled via this rather than the registry in future. However for anyone else having the problem of it not resting or resting too much, check this first as it might be an easier way of managing this issue.


Answers

  • JackE
    JackE ACE Posts: 44,891 Trailblazer
    The hum you hear is 50/60Hz AC that suggests EITHER your charger is not well grounded (if it has a separate 3rd ground prong on the plug) ---OR--- the AC wall receptacle the charger is plugged into is not well grounded --- OR ---- polarity of the AC wall receptacle is reversed. If the charger has a 2 prong plug that isn't polarized, the hum will probably disappear if you reverse it in the AC wall receptacle. Jack E/NJ

    Jack E/NJ

  • CARLTONBP
    CARLTONBP Member Posts: 14

    Tinkerer
    Sorry it's the laptop making the noise. I'm just wondering what the settings are for on battery that are different so I can replicate on ac. Thanks
  • JackE
    JackE ACE Posts: 44,891 Trailblazer
    Yes, the laptop will make the noise through the speakers. The hum is amplified by the laptop and fed into the speakers. Try reversing the plug in the wall receptacle. Jack E/NJ

    Jack E/NJ

  • CARLTONBP
    CARLTONBP Member Posts: 14

    Tinkerer
    Thanks for that. I have uk plug but I'll try plugging it in to various points.
  • JackE
    JackE ACE Posts: 44,891 Trailblazer
    OK. But please report back one way or another. Jack E/NJ

    Jack E/NJ

  • CARLTONBP
    CARLTONBP Member Posts: 14

    Tinkerer
    I've recently had upstairs rewired so I tried it there. Seemed to work. However downstairs is a bigger job and I'm going to do it when the whole space is renovated. So I tried a really good solid beast of an extension lead I have, it has a grounded light etc. And that seems to have worked.

    It's been 10mins and the white noise hasn't started again so fingers crossed.

    Thanks
  • CARLTONBP
    CARLTONBP Member Posts: 14

    Tinkerer
    Took the dog for a walk, noise was there when I got back. I will later on tonight try upstairs for longer.
  • JackE
    JackE ACE Posts: 44,891 Trailblazer
    >>>downstairs is a bigger job>>>

    Ouch! Sounds like downstairs has the old style ungrounded 3-wire outlets probably with integrated 3-wire cables. Belfast codes probably call for integrated 4-wire cables now. So you can't get away with just running a separate ground and keeping the 3-wire cables. So yes a bigger job. And much pricier I might add.   :o   Thanks for the report. Jack E/NJ

    Jack E/NJ

  • JackE
    JackE ACE Posts: 44,891 Trailblazer
    Sounds like you have an ungrounded ***something or other*** intermittently running downstairs that may be feeding back interference into your breaker box if it's handling both the re-wired upstairs and the old-wired downstairs.  Perhaps a fridge? If the noise re-appears, try unplugging appliances one by one to see which one or more might be causing it. Jack E/NJ

    Jack E/NJ

  • CARLTONBP
    CARLTONBP Member Posts: 14

    Tinkerer
    Upstairs is isolated from downstairs, it's on a new rcd and barely anything is connected to it. Didn't have time to try it last night. The wires in the kitchen are newer than those in the living room. So I have options to try. I'll let you know. Thanks
  • CARLTONBP
    CARLTONBP Member Posts: 14

    Tinkerer
    Answer ✓
    Found the solution - it was on an older thread you posted on, except I'm doing the opposite.
    I bought a non-grounded power supply. Took ages, had to check for safety, find a reputable safe one. Turns out I didn't need it but at least I have one.

    Using HDDscan I worked out the HDD wasn't spinning down even though it sounded like the spindle was resting.
    W10, progs etc are on a 512gb ssd which is in the old optane port. I still have the 1tb hdd (toshiba) that came with the laptop on which are a few files but no progs.

    His problem is the opposite of mine, he's using the HDD as his main drive and for him it was constantly spinning up and down which I know is very annoying as I had HDpharm on an old laptop to stop this.

    What I did
    1. I enabled all the advanced power settings that Acer restricted access to, (not impressed Acer) 13th post down. Not sure if that has changed anything but it's nice to have access.

    2. THen 9th post down I added "EnableAPM"=dword:00000000 to the registry.
    I guess it's a legacy setting from the optane and HDD being main drive.
    The HDD now rests after 25seconds.

    Possible alternative
    I had a look at Intel Rapid storage app. I noticed under performance, there is now enable/disable link power management ( don't think it was there before). So I think this can now be controlled via this rather than the registry in future. However for anyone else having the problem of it not resting or resting too much, check this first as it might be an easier way of managing this issue.


  • JackE
    JackE ACE Posts: 44,891 Trailblazer
    Congrats. Thanks for the report. Jack E/NJ

    Jack E/NJ

  • CARLTONBP
    CARLTONBP Member Posts: 14

    Tinkerer
    JackE said:
    Congrats. Thanks for the report. Jack E/NJ
    Thanks for all your help. This forum is one of the key reasons why I chose Acer. It's been very useful. My laptop is now really quiet. I really didn't think it was the HDD because I heard the resting clunk but I guess it was still spinning, my mistake.

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