1 Reply Latest reply on Feb 13, 2010 2:49 AM by francisxavier.p

    Fan cannot running at full speed, DQ45CB



      Recently i bought a DQ45CB to replace my P45 system. My processor is E8400 cooled by stock fan running with Vista x64.


      My problem is, the stock fan cannot run faster than 1000 rpm when I connected the processor power to 4-pins processor fan header on the motherboard. Even in stress test with 100% cpu utilization and the temperature reach 78c , the fan still run with 1000 rpm. But the fan manages to get 1500 rpm when it connected to rear fan header. However, it stays at 1500 rpm all the time.


      I believe, the maximum speed of E8400’s HSF is 2000 rpm, but it never achieve that. The maximum I get is 1500 with rear fan header connection.


      The only way the fan run 1500 rpm with the 4-pins fan header connection is by disable Intel Management Engine. But with this Intel ME disable, I can’t monitor the fan speed in vista and the information is minimal.


      I also try to connect a 120mm fan to the rear fan header but the 120mm fan ramping up and down continuously. The speed is not stable. If I use 120mm L.E.D. fan, the LED will keep blinking like it doesn’t get enough power.


      So, how can I solve this problem? The temperature is too hot. Is the any software I can use to change bios setting in Vista x64. From intel website, I only see software for x32 windows not x64. I believe the problem is with the Intel Quiets System Management. It fail to increase the fan speed even the processor is too hot.


      Please help.


      Thank you .

        • 1. Re: Fan cannot running at full speed, DQ45CB

          I use a D945GCNL board. Not sure how the BIOS differs with your motherboard. In BIOS under Advanced --> Boot Configuration, You have some thing  called CPU Fan control and Sytem Fan control. Disable both and your  System as well as CPU fan will be running almost their maximum speeds.  You can use the Speedfan utility to check the Fan speeds in Windows.

          When you disable the sytem fan control in BIOS your LED Fans will run with the LED On with their maximum speed.

          Hopes this helps you a bit.


          My CPU Fan  runs @ 2380 rpm and System fans both run @ 2700 rpm