Lowering Radeon 6870 fan noise in OS X Lion

While in Windows 7 the Radeon 6870’s GPU fan is almost inaudible under idle conditions, the fan is clearly audible in OS X Lion. In OS X the GPU fan is permanently changing its speed which creates quite some bothersome noise. If you can’t live with that noise, here’s a tip for the not-so-faint-of-heart about how to modify the fan control curve of your Radeon graphics card. This involves flashing your graphics card’s BIOS using an optimized temperature/fan-speed map. Ain’t that cool? :-)

Follow this guide on insanelymac.com. But instead of using the look-up table, you just select “set all fan settings to recommended values”. Flash the BIOS and you’re done. No more fan noise¬†under idle conditions in OS X Lion.

8 replies on “Lowering Radeon 6870 fan noise in OS X Lion”

  1. Hi again!
    Well, it went well, but ther were some quirks to it. First of all,I did this in my old pc. I installed the correct drivers, and then used GPU-Z to backup the original bios (Barts for 6850).
    I then opened my saved backupbios RBE and made my own profile, at 50degrees, 25%fan at 85 degres 100%fan iirc. I saved this modded bios with new name.
    I then used atiwinflash to flash the bios. Restart. I monitored the card temperature for an hour before setting it in the Mac Pro 1.1, and voil√° – quieter Mac! It still not ultra silent (…) but now I can live with it from before. Important, I use imenu (?)and cwp (?) to monitor the temps and control fanspeed on all but the GPU. The temperatures changed a bit after i lowered the gpu fan, so i had to make adjustments. Right now I run all fans on 850 rpm.
    Thanks from Sweden

  2. This sounds very interessting, I have contacted xfx support on this issue too on my xfx6850BE card, running in a “real” Mac Pro 1.1 (Lion 1.7.3) I have to loud fanspeed (annoying high-pitched sound). I will try get it into my old pc, and follow theese tricks to lower the fanspeed in the bios.
    How do I know that core and quartz is running on the card is a question of mine, I only use the machine for photoshop (no games and stuff). (Sorry not english-native-tounged :) ) Greets from Bokskorpionen, Sweden

  3. Great, thanks for your answer. :)

    I saw on a forum, maybe it was on techpowerup.com, that people flashing 6800 series cards where having problems when loading Windows ( non Hackintosh users ), I normally don’t use Windows anyway but wanted to ask you if you experienced that too?


  4. Hi, thanks for the answer. I checked Club 3D’s website, and found a few (4):
    Radeon HD 6870
    CGAX-68724 – PCI Express 2.1 – 1024MB – GDDR5 – 256BIT
    Radeon HD 6870
    CGAX-68724F – PCI Express 2.1 – 1024MB – GDDR5 – 256BIT
    Radeon HD 6870 Overclocked Edition
    CGAX-68724O – PCI Express 2.1 – 1024MB – GDDR5 – 256BIT
    Radeon HD 6870 Eyefinity 6 Edition
    CGAX-68748M6 – PCI Express 2.1 – 2048MB – GDDR5 – 256BIT
    Where only the CGAX-68724 uses reference design, did you get that one?


  5. Hi, I also have a Asus P6T mobo ( V2 Deluxe version ) and I’m considering getting a Radeon 6870 graphics card to replace my Geforce GTX 260 because it’s the noisiest part of my computer.
    May I ask if you got a reference design 6870 to get the fan profile flash to work? and which manufacturer/model did you get?
    Thanks for your article and help.

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