Sony BX series BIOS mod to lower fan noise

Discussion in 'BIOS Mods' started by SonyBXUser, Mar 17, 2010.

  1. SonyBXUser

    SonyBXUser MDL Novice

    Mar 17, 2010
    #1 SonyBXUser, Mar 17, 2010
    Last edited: Mar 17, 2010
    Hi all,

    I'm new to this forum but not entirely new to BIOS modding. About 8 years ago I did a few mods for some Tyan desktop boards, I think it was using AMIBCP and CBROM at the time.

    These days I'm out of tune but that's not to say unwilling to put in the effort to get results.

    I have a Pentium M based (as there are also Core Duo models) Sony BX series laptop that has its CPU fan spinning more than necessary. I believe it's a habit of Sony to do this on various models of their laptops.

    Anyhow, I want to mod the BIOS to get the fan spinning but at higher CPU temps so to maintain a quiet laptop in all but the most stressful of usage cases (i.e. something that stresses the CPU a lot thus produces more heat).

    I think this can be done via editing some values in the WPH file in a hex editor, i.e. the values that tell the fan from which temp to run the fan at speed XYZ etc. Maybe I'm wrong, what do you think? I know that this has been done before to alter register values which in turn control MCH configuration (i.e. memory speed/timings etc.).

    Or another options would be to bring in the power management code from a newer BX BIOS as I've noticed more recent versions of the VAIO power management software allow changing the CPU fan speed as well as cooling profile (i.e. quiet, performance, balanced etc.). I've tried it on my BX and they don't work, I think it's because the software needs to interact with a BIOS tuned with these settings.

    How can I (we) crack this one? It's a common problem yet as far as I can see no one's fixed it yet. Sony did release a newer BIOS that simply spins the fan at medium all the time but even this is loud (far too loud for when typing, emailing, browsing or even watching a DVD where the CPU is hardly stressed at all). Maybe this "updated" Sony BX BIOS could be used as the base and simply slightly tweak the fan to run at a constant "below medium" speed.

    I've downloaded the BIOS tools from within this forum but when I try opeining up the Pheonix BIOS Editor I just get an OCX error which reminds me of the Visual Basic days :)

    Any help would be appreciated. Please tell me how I can contribute, i.e. what files/data would you like to look at (if any)?

    I've uploaded the latest Sony BX series Intel 915PM chipset BIOS to the link below:

    Thanks in advance,
  2. brooksie

    brooksie MDL Novice

    Apr 11, 2010
    I have a BX297 and the fan is very loud, even with the bios update.

    Did you manage to work out how to change the values in the bios?


  3. SonyBXUser

    SonyBXUser MDL Novice

    Mar 17, 2010

    No, unfortunately I didn't.

    The best one can do it seems is use some software to lower the CPU voltage thus heat. I think the best is Notebook Hardware Control although I think there's another one called RightMark etc.