ATi Radeon HD 4870 & 4850 Fanfix

* UPDATE * This has been fixed in Catalyst 8.10 Release, you can manualy change fanspeed in this catalyst 

http://game.amd.com/us-en/drivers_catalyst.aspx

this is how to fix the fan problem, it should be fixed in next months drivers, i asume (catalyst 8.7)

0. Open Catalyst Control Center
1. Go to ATi Overdrive and enable it, then apply
2. Then to Profiles Manager in Profiles
3. Enter Fanfix as name of profile, then select ATI overdrive in Compostion
4. Select Desktop Shortcut in Activation
5. Save and Close
6. Open Fanfix.xml in

XP: C:\Documents and Settings\[Username]\Local Settings\Application Data\ATI\ACE\
Vista: C:\Users\[Username]\AppData\Local\ATI\ACE\

7. Change Automatic to Manual under “FanSpeedAlgorithm_0″, then change “FanSpeedPercentTarget_0″ to the speed you want
8. Run the desktop shortcut and done

you can do for diffrent speeds just make new profiles, and then you can drag the desktop shortcut to startup folder in startmenu to get it to automaticly load on startup

Catalyst 8.7 will be out on 15 july

if you make a profile in catalyst after turning on Overdrive( make sure clock and memory settings are correct). You can then go to the file “C:UsersBretwareAppDataLocalATIACEBretware. XML. the xml file will have the same name as the catalyst profile you saved. right click and hit edit.

Change the value to “manual” and Want value to “65″Save the file then reload your profile in catalyst.

65% seemed perfect for me, 70% was loud but you may need it if your case has poor air flow.

You will may have to select the profile everytime you start the computer, but it will work until there is a fix or better info so i can figure how to change the auto target temp.
Good Luck ,bretware

thx bretware
http://forums.guru3d.com/showthread.php?p=2751569#post2751569