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    5-Second Fan Pulsing Fix In New T520 BIOS (possibly W520, T420(s), X220)

    Discussion in 'Lenovo' started by ferganer80, Jul 10, 2011.

  1. ferganer80

    ferganer80 Notebook Consultant

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    I have been testing the beta (1.28) BIOS for T520 since yesterday. The new BIOS seems to solve the 5-second pulsing fan problem and makes the fan quieter. However, the new BIOS results in the CPU throttling. I hope they will fix the CPU throttling problem and we will finally get workable and enjoyable laptops.

    I also know that the beta BIOS for W520, T420, T420s, and X220 also addresses the fan pulsing problem and is discussed on Lenovo Forums.

    If you would like to help test the new BIOS, please, contact JameZ on Lenovo Forums.

    See pages 7 and 8 of the following thread:

    T520 fan plusing noise every 5 seconds - Page 8 - Lenovo Community
     
    ferganer80, Jul 10, 2011
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  2. kirayamato26

    kirayamato26 Notebook Deity

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    Yep, it is also fixed on the W520. The test BIOS (1.26) was released a few days ago on the forums by JameZ. But yeah, it results in CPU throttling on battery. If Lenovo fixes that, then everything is good to go.
     
    kirayamato26, Jul 10, 2011
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  3. ferganer80

    ferganer80 Notebook Consultant

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    Thanks kirayamato26. Great to hear that they are fixing the pulsing problem across the board.

    However, unlike in your case, my T520 throttles both on battery and AC power.
     
    ferganer80, Jul 10, 2011
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