Control the fan speed of your Radeon HD 4850/4870

by Reads (5,530)

The ATI Radeon HD 4850 and 4870 are certainly delivering excellent performance, but the heat level of the cards is somewhat alarming. A utility to manually control the fans has been created by bretware, a forum user at Guru3D.

There are only a few simple steps needed to get manual fan control working:

  1. In Catalyst Control Centre, make sure clock and memory settings are correct and turn on Overdrive
  2. Create a Catalyst Control Centre profile called “fanspeed”
  3. Navigate to C:\Users\UserName\AppData\Local\ATI\ACE\ and you’ll find an XML file titled “fanspeed”, open the file in Notepad or your preferred editor. The file should resemble the following:

    <Feature name=”FanSpeedAlgorithm_0″>
    <Property name=”FanSpeedAlgorithm” value=”Manual” />
    <Feature name=”FanSpeedRPMTarget_0″>
    <Property name=”Want” value=”0″ />
    <Feature name=”FanSpeedPercentTarget_0″>
    <Property name=”Want” value=”65″ />

  4. As shown above, change the “FanSpeedAlgorithm” value to Manual and the “FanSpeedPercentTarget” value to 65 (or your preferred fan speed in percentage)
  5. Save the file and reload the “fanspeed” profile in Catalyst Control Centre.

One of our forum members, Iceman0124, is seeing load temperatures top out at less than idle temperatures with the auto-fan control, manually setting the fans to 55% speed. See the thread for more information.

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