I did this to install MorphOS on a PCIe G5 PowerMac
Required Hardware
- Mac-specific 6-pin PCIe power cable
- Radeon X1900GT 256Mb, these are getting rarer but do come up on eBay and Thrift shops
- PC setup with PCIe Slot and power (Capable of booting from USB)
- USB Drive ton install a DOS image on
Flashing Steps
- Setup a USB device to boot the PC from with MS DOS 6.2.2 (FreeDOS doesn’t work) balenaEtcher can be used to restore an image of onto a spare USB Drive.
- Download ATIFlash 4.07 from TechPowerUp (you will need to click the ‘Show older versions‘ button to see it).
Click “Show older versions”
4.07 (Versions not in order)
- Now download the Retail : Radeon X1900 GT (available at the bottom of the ‘Original ATI PPC ROMs‘ list).
- Create an ATI directory/folder in the root of the DOS USB Drive
- Move ‘atiflash.exe‘ to the ATI directory on your prepared DOS USB drive. Rename ‘Radeon X1900 GT rev 109.rom‘ to ‘x1900GT.rom‘, and move that to the same place.
I have a pre made disk image here Dos6.22 ATI.img
- Install X1900GT into the PCIe of the x86 PC. The X1900 GT itself can provide the video output from here on; using an additional PCI graphics card is not necessary. If the PC’s power supply does not have a 6-pin PCIe power cable available, use an adaptor; these are available from the common online stores!
- Plug the DOS USB drive in, and boot from it.
at the prompt type
cd ATI
then to check the contents type
dir
You should see ‘X1900GT.ROM’ and ‘ATIFLASH.EXE’ listed.
We need to know the adaptor number, type
atiflash -i
note the adapter number of the installed X1900 GT, which is identifiable by the ‘R580+’ tag in the middle column.
Usually, the adapter number to the far left of the ‘R580+’ will read ‘0’, provided the card was installed to the PC’s first (or only) PCIe x16 slot.
Note In the following steps it assumes the adaptor number to be ‘0’, replace the 0 with the correct adaptor number if it differs.
Optional If you want to backup the X1900’s original ROM to the current directory, type
atiflash -s 0 x19back.rom
To flash the card type
atiflash -p -f 0 x1900GT.rom
- -p tells atiflash to program the card’s ROM
- -f tells it to force the program
- 0 tells it which adapter to program (change this if your adaptor number differs)
- x1900GT.rom is the ROM it should use to program the card with
Your screen may flicker for a couple of seconds. Afterward, it should tell you that the flash was successful, at which point use the power down the machine.
Remove the newly-flashed X1900 GT from the PC, and install it into the G5.
If all went well, the Apple logo should come up, and you should now be in Mac OS X. Verify the GPU information via Graphics / Displays in System Profiler, and rejoice!
You have successfully flashed a graphics card completely on your own, and now possess a Radeon X1900 GT PPC Mac Edition.
