Need help flashing 7800 GTX 512 for Power Mac G5

[takeshi7]

Hi,

I've been trying to flash my XFX 7800 GTX 512 MB so that I can use it in my G5 quad. I've tried flashing every ROM from this thread:
https://forums.macrumors.com/threads/1552556/
When I try to run nvflash from a bootable USB disk it says that "this program can't be used in DOS mode" so I've been running nvflash from within Windows 7. I was able to back up the ROM file that's on the card with nvflash, but when I try to flash a new ROM it beeps twice and nothing happens (I think I see a command prompt window open for a split second though). Any help would be greatly appreciated.

 

[ifrit05]

Never use Windows to flash BIOS/ROMs!
What kind/version of DOS are you trying to run? nvflash should run in DOS mode (it is a DOS program).

Have you tried FreeDOS?

 

[takeshi7]

I was using a windows 98 boot disk created with the HP USB Disk format tool.
http://download.cnet.com/HP-USB-Disk-Storage-Format-Tool/3000-2094_4-10974082.html

I was using nvflash 5.142 and it definitely wouldn't run within DOS on the USB stick, but it did run within windows.
http://www.techpowerup.com/downloads/2258/nvflash-5-142-for-windows/mirrors

I was able to at least back up the ROM that is on the 7800. nvflash would then recognize that the original PC ROM was compatible with the card, but when I tried to open any of the Mac ROMs with nvflash it would close and flash a message on screen along the lines that the rom isn't compatible.

 

[ifrit05]

You could try an older version of nvflash, that might work. I know I had to use an older version to flash my FX 5500 to a Mac Rom.

 

[666sheep]

Nvflash for Windows won't work in DOS
Version 5.67 will be fine for 7800GTX.

 

[takeshi7]

OK I figured it out. I was indeed using the windows version of nvflash. I found the DOS version 5.63 here and when I booted from USB it worked:

http://downloads.guru3d.com/nvFlash-v5.63---NVIDIA-Firmware-Utility-download-1862.html

Thank you both for your help! I was about to give up and smash the card.

 

[ifrit05]

Glad to hear it!

 

[Melchieor]

Does anyone know if the Dell version of the Geforce 7800 GTX 512 work with the flash available? I tried with nvflash and the firmware available on macintoshgarden and also on another thread here and neither worked. After flashing I would install on the G5 and it would only show a blank screen and no chime. I did manage to flash a Quadro FX 4500 without issues.