Fix bad FPS/no fan on Radeon 4870 without flashing!

[h4ck1nt05h]

So tonight, I decided to tackle my video card's fan not working, and managed to get over 1000 more fps in OpenGL Extensions Viewer with 8x multisampling on 10.6.6! Games run much smoother, and I'm not worried about toasting my card in the process.

 

I'm using an XFX ATI Radeon 4870 512mb. This should work with the 1GB as well, not sure about other brands, but worth a shot!

 

Testing was done with OpenGL Extensions Viewer and 8x

 

Before:

 

After:

 

What's needed:

* PC EFI (thanks Netkas!) - PC EFI 10.6 If you don't know how to install this, if you are using Chameleon, replace the boot file in the root of your startup partition.

* Knowing how to edit plists - Know how to use a text editor...

* ATI Radeon 4870 - No flashing required!

 

How to do this:

* Download PC EFI if you aren't already using it, decompress it, and replace the boot file in your startup partition.

* Download the attached ati_9440_1002.zip and unzip it.

* Put the ati_9440_1002.rom file in your /Extra folder.

* If you have any enablers installed, remove any EVOEnabler or ATY_Init from your /Extra/Extensions and /System/Library/Extensions and delete /System/Library/Caches/com.apple.kext.caches/Startup/Extensions.mkext (only do this if you were using EVOEnabler or ATY_Init!)

* Modify /Extra/com.apple.Boot.plist and add the following lines:

	<key>GraphicsEnabler</key>
<string>y</string>

then find

	<key>Kernel Flags</key>
<string></string>

if you have things inside <string>, leave them, put a space, and add/if you don't have anything in there, just add between the <string> tags:

-useatirom

 

Reboot, and cross your fingers!

 

What I did was take a ROM dump from a XFX 4870 1GB, modified the clock speeds to be correct, added manual fan control triggered at certain temperatures, and saved the new ROM. PC EFI will then load the ROM BIOS image at boot, and you have a much more functional Radeon 4870!

 

Cross your fingers, reboot, and you should have much better performance and the fan works!

 

Let me know if this works for you too! Feedback is appreciated!

ati_9440_1002.zip

[el lissitzky]

can you elaborate on how you manually set the fan timings?

 

i have a 4890 and the fan won't spin up at all so it's running hot.

 

you can load the video card bios through pc efi?!