there are two kext files. one of them is aty_init.kext another one is ATI2600controller.kext.
ATI2600controller.kext has been added device id 9589x1002 and it started working now
it is really great happiness!
download the kext files and use next wizard to install these kexts and don't forget to clear the cache and repair permissions.
Mainboard is gigabyte EP45-DS3R
I have Sapphire RADEON HD 2600 XT (256MB) I tried these kexts, it didn't work, I even tried disabling GraphicsEnabler and many other tricks. none of them worked!
If there's a proper way to do so, please share it.
P.S : too bad, my XFX 8800 GT stopped working due to fan cables problem. It used to work flawlessly with GraphicsEnabler=Yes ONLY.
I wish there was a way to buy another one, the city where I live is full of retards who think that silent cards are the best for gaming.