Please report all spam threads, posts and suspicious members. We receive spam notifications and will take immediate action!
Results 1 to 2 of 2

Thread: What's the difference between PWM and "auto" fan control in BIOS?

  1. #1
    Join Date
    Nov 2012

    Default What's the difference between PWM and "auto" fan control in BIOS?

    Not sure if this is a standard distinction, I can't control the CPU fan (which has 4 pins and the system can control it under load) with Speedfan with either setting. FWIW I have the GA-M55SLI-S4 1.0 with the Beta F11j BIOS.

  2. #2
    Join Date
    Dec 2010
    Near Toronto but not in it

    Default Re: What's the difference between PWM and "auto" fan control in BIOS?

    PWM is the most sure way of confirming fan speed rotation. if that fan is commanded at 1500rpm and the MB senses that the fan is spinning at 1450rpm it will compensate the difference, increase the voltage and make it 1500RPM. possibly with your MB being set to Auto is disabling the control from windows?

    in your MB, Auto sets the follwing; BIOS autodetects the type of CPU fan you installed and sets the optimal CPU Smart FAN control mode for it. (Default Value)

    But for this to operate properly you also have to enable CPU Smart FAN Control, and your CPU has to support it.

    I would try to disable CPU Smart Fan and then set the fan control to PWM and then see it you can control it in windows. only issue with that is if overclocking, you may not be adaquately cooling the system during bootup.

    but it could be worth a try.

    Main Rig
    OS = Win8.1
    CPU = i7-980X @ 4.17Ghz 144x29 cooled by custom Loop
    Mem = 12GB 2000Mhz corsair Dominator GT at 2010Mhz @ 9-10-9-27-2T
    MB = Gigabyte GA-X58A-UD5 v1.0 with F6 Bios - Dead Board
    MB = EVGA X58 Classified3 e770
    GPU = 2x Sapphire r9 290x in xfire
    HD = 4x PNY 120GB Raid 0
    Storage = 2TB WD Black
    PSU = EVGA SuperNOVA 1300w
    Case = Cooler Master HAF-X 945

    HTPC / Home Server
    OS = Win7 64Bit running XBMC HTPC Front end with Windows Server 2011 Virtual Machine with 8GB ram assigned for homer server with exchange
    CPU = AMD 1090T
    Mem = 16GB 1600Mhz Kingston RED Limited Edition running at 1600Mhz
    MB = Gigabyte 790FXTA-UD5
    GPU- EVGA GT210
    HD = too many to count, but about 5TB of storage all together including backup
    PSU = Corsair TX750
    Case = Too embarrassed to mention.

Thread Information

Users Browsing this Thread

There are currently 8 users browsing this thread. (0 members and 8 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts