Maybe I made one step forward, but still no acceleration for this card.
After installing mac os x 10.6.4 update, my ASUS EAH5450 was working but without acceleration. Only 1 resolution, the one I inserted in com.apple.Boot.plist. No resolution change possible.
After installing mac os x 10.6.6 update, I got black screen before entering the desktop, even using UseAtiROM option with 1002_68f9.rom in EXTRA folder.
So, I replaced the ati drivers in S/L/E with the drivers downloaded from this post:
and now no more black screen. I can see my desktop. My card is working exactly like before 10.6.6 update. But acceleration and resolution change are still not working.
I also added device id in Ati5000controller.kext, but still no acceleration and resolution change.
What else must I do for having acceleration and resolution change?
p.s. during boot in verbose mode (-v), I noticed that at some point it says:
not loaded kext com.apple.Ati5000controller.kext - file not found................
but that file is present in S/L/E