ok ppl I brought 2day Asus6870 1GB .. not installed yet ! I still have 4890 inside
what should I do to make it works and also have Boot and multi boot function
4890 I will change bios to windows and install it in kids computer
need advice
BR
Boy, you really like making things complicated, huh?
I am not sure why this info never seems to stick but when a card gets an EFI ROM made for it, it is really the original PC BIOS with an EFI "introduction" for the Mac Pro,
The PC BIOS is what runs the card, and it is still 100% there and capable of running card in Windows. This applies to 2600XT, 3870, 4870,(4890) 5870 and now even the 6870. You can pop any one of those out of a Mac Pro and into a Windows machine and it won't even hiccup. The ONLY exceptions were the original Mac EFI cards, the X1300 and X1900XT, those had EFI only ROMs on them and will NOT work in a Windows PC.
And this is why you don't need to lift a finger to have the 6870 work in Mac Pro.
Install and boot. As long as you have 10.6.8 or later, the card will fire up when machine reaches desktop. Mac Pro cards are RUN from PC BIOS, the EFI you add just introduces them and gets keys set.
If you have a Mac Pro 1,1 or 2,1 you will need to use ATY_Init to fix the issues.
If you have 3,1 or later, you will need to use ROM Creator to .....wait for it......create a ROM. Unless it is an XFX card, you will likely need DOS or a PC to flash it.
Bingo. done
Only issue you might run into is 4890 "patch" interfering. Remove it if so.