Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

MDBenson

macrumors newbie
Original poster
Dec 16, 2022
23
4
Hi,

I bought a EVGA GeForce 7800 GT PCIe card with the aim of flashing it for my G5 quad.

Unfortunately the EVGA card only has a 64k ROM whereas the ROM I obtained from TheMacElite is for a 128k ROM and its actual size is around 68k, and the flash fails as it runs out of EEPROM space.

Is there any solution to this issue or am I outta luck?

Also I have a non-double-sided Quadro FX4500 from my Dell workstation - did anyone ever patch the QFX4500 ROM to work with those cards?
 

joevt

Contributor
Jun 21, 2012
6,699
4,089
I'll try to make a compressed Nvidia ROM. The problem is, it won't work if there are parts in the middle of the ROM that the hardware or software requires to be uncompressed. I'll leave the softstrap stuff at the beginning of the ROM uncompressed.
 

MDBenson

macrumors newbie
Original poster
Dec 16, 2022
23
4
Wow, thanks. It'll be awesome to at least try it.

It really doesn't need a lot, it's only about 4-5k over the ROM size if that makes any difference?
 

joevt

Contributor
Jun 21, 2012
6,699
4,089
Attached is a 64KB Nvidia 7800 GT ROM (Test3) based on the Test2 version I created at #722 so it should also work on Old World Macs (with PCI to PCIe adapter) but it's untested.
The decompression uses the Open Firmware lzss implementation created by @dosdude1 (links in the source). The compression uses code from Apple's latest kext_tools (also included).

In my fork of the dingusppc emulator, the 64KB Nvidia 7800 GT ROM at least loads so you can see the devices and properties in the Open Firmware device tree. It has similar behaviour in dingusppc to the uncompressed 7800 #21 rom (the Test2 version).

Since the ROM is based on the Mac version of the card, it might have different timings than other cards such as yours. One would usually use some kind of utility or set of instructions to copy the timings from the original PC ROM into the Mac ROM? You would have to do that with the uncompressed Mac ROM and then recompress it. Does your 7800 GT have 256 MB VRAM?

There's some mention of the Quadro FX 4500 in the linked thread. You can search the first post of that thread for related links.
 

Attachments

  • 7800 #23.zip
    95 KB · Views: 11
  • joevt-lzss.zip
    15.6 KB · Views: 9

MDBenson

macrumors newbie
Original poster
Dec 16, 2022
23
4
Hi,

Yes my card has 256MB RAM.

I’ll give the ROM a test as-is and report back, I’ve never done a PC-to-Mac flash before so I wasn’t aware that the timings could potentially need copying. I’ll cross my fingers and hope the Mac ones work and if not I’ll drop back to the original ROM. I do have the PC ROM backed up if that’s any help.
 

MDBenson

macrumors newbie
Original poster
Dec 16, 2022
23
4
Hmmm… I must be doing something wrong here. NVFlash.exe segfaults when I try to write the ROM image.

I am using nvflash.exe 5.67 though so I might need something older?

The GeForce 7800 GT is the only NVIDIA GPU present at index <0> and I am using the Intel IGPU for the DOS display during flashing, although I got the same result using the 7800 GT for the display. I can use the same command to write the PC ROM back with no issues.
 

Attachments

  • image.jpg
    image.jpg
    385.6 KB · Views: 18
  • image.jpg
    image.jpg
    382.8 KB · Views: 16

joevt

Contributor
Jun 21, 2012
6,699
4,089
I've never flashed an Nvidia rom either.

Is nvflash trying to examine the contents of the ROM inside the compressed area? Maybe I need to split it up and keep the BIOS stuff uncompressed...
 

MDBenson

macrumors newbie
Original poster
Dec 16, 2022
23
4
It does read several properties out of the ROM image when it's flashing (Vendor and Board IDs etc) so it may be that's the issue.

The segfault is immediate too, not during thee flash process.

Appreciate the help :)
 

MDBenson

macrumors newbie
Original poster
Dec 16, 2022
23
4
Okay, progress!

It flashed okay with nvflash.exe 5.31

It shows firmware framebuffer stuff.

EDIT: booting an OS dumps me at an OFW prompt with an error.
 

Attachments

  • image.jpg
    image.jpg
    366.7 KB · Views: 23
  • image.jpg
    image.jpg
    974.5 KB · Views: 26

joevt

Contributor
Jun 21, 2012
6,699
4,089
Which OS? Do you have a real 10.4.11 or 10.5.8 to try? Does the Apple logo appear?
Does .time-stamps in Open Firmware show anything interesting?

The attached has a minor change which might or might not address the issue (probably not).
 

Attachments

  • 7800 #24.zip
    95.3 KB · Views: 8

MDBenson

macrumors newbie
Original poster
Dec 16, 2022
23
4
I am using known good 10.4.6 and 10.5.0 DVD install images from a FW400 SSD. They have been used to install multiple PPC systems including a G5.

There’s no logo it stops immediately after the screen-mode change is attempted from OFW to OS X boot.

Is .time-stamps an OFW command? Can you elaborate on that?
 

MDBenson

macrumors newbie
Original poster
Dec 16, 2022
23
4
UPDATE: Tried #24 and no change, as you suspected.

Code:
.time-stamps
Code:
.time-stamps\
and
Code:
.log
commands all return
Code:
unknown word
errors
 

joevt

Contributor
Jun 21, 2012
6,699
4,089
I think you need to do
setenv fcode-debug? true
and restart to use .time-stamps

I'll do some testing on my side but it might take a few days.
 

joevt

Contributor
Jun 21, 2012
6,699
4,089
I got my Quad G5 with 7800 GT setup and working. Before I start flashing, can you do one test for me:

Boot into Open Firmware.
Type .line-help for a list of supported keys for the nvedit command.

Type nvedit to edit the nvramrc script.

Enter the following lines (include all the spaces):
Code:
.s cr
." [ probe-all" cr
probe-all
." ] probe-all" cr
.s cr
install-console
banner

Press Control-C to exit nvedit.
Type nvstore to save the edited nvramrc.
Type setenv use-nvramrc? true
Type system-restart to restart. Boot into Open Firmware, and describe what you see on the screen before the Open Firmware version information.
 
  • Like
Reactions: MDBenson

MDBenson

macrumors newbie
Original poster
Dec 16, 2022
23
4
I got my Quad G5 with 7800 GT setup and working. Before I start flashing, can you do one test for me:

Boot into Open Firmware.
Type .line-help for a list of supported keys for the nvedit command.

Type nvedit to edit the nvramrc script.

Enter the following lines (include all the spaces):
Code:
.s cr
." [ probe-all" cr
probe-all
." ] probe-all" cr
.s cr
install-console
banner

Press Control-C to exit nvedit.
Type nvstore to save the edited nvramrc.
Type setenv use-nvramrc? true
Type system-restart to restart. Boot into Open Firmware, and describe what you see on the screen before the Open Firmware version information.
Is the "cr" Part of the script or indicating for me to enter a carriage-return (i.e. press enter)
 

joevt

Contributor
Jun 21, 2012
6,699
4,089
The attached should fix the problem with mem-free.

The attached also fixes another problem with Old World ROMs. In Open Firmware 1.0.5, the $find word would leave an extra item on the stack if the search doesn't succeed.

I haven't yet tried to flash it. I'll try that tomorrow. Can I use Windows 10 to flash it?
 

Attachments

  • 7800 #25.zip
    241.3 KB · Views: 10

MDBenson

macrumors newbie
Original poster
Dec 16, 2022
23
4
The attached should fix the problem with mem-free.

The attached also fixes another problem with Old World ROMs. In Open Firmware 1.0.5, the $find word would leave an extra item on the stack if the search doesn't succeed.

I haven't yet tried to flash it. I'll try that tomorrow. Can I use Windows 10 to flash it?
Easiest way is to use Rufus (ISO copying util) in Windows to make a FreeDOS USB stick, then put nvflash.exe and the ROM onto the USB and boot from it. I am using a spare motherboard and CPU my dad had laying around, but any PC should be okay booting FreeDOS.
 

MDBenson

macrumors newbie
Original poster
Dec 16, 2022
23
4
I got my Quad G5 with 7800 GT setup and working. Before I start flashing, can you do one test for me:

Boot into Open Firmware.
Type .line-help for a list of supported keys for the nvedit command.

Type nvedit to edit the nvramrc script.

Enter the following lines (include all the spaces):
Code:
.s cr
." [ probe-all" cr
probe-all
." ] probe-all" cr
.s cr
install-console
banner

Press Control-C to exit nvedit.
Type nvstore to save the edited nvramrc.
Type setenv use-nvramrc? true
Type system-restart to restart. Boot into Open Firmware, and describe what you see on the screen before the Open Firmware version information.
Apparently not a lot…
 

Attachments

  • IMG_7150.jpg
    IMG_7150.jpg
    437.5 KB · Views: 13
  • IMG_7151.jpg
    IMG_7151.jpg
    504.3 KB · Views: 15

MDBenson

macrumors newbie
Original poster
Dec 16, 2022
23
4
I tried a manual `probe-all` from the OFW prompt and it threw a memory error with the #24 ROM
 

MDBenson

macrumors newbie
Original poster
Dec 16, 2022
23
4
The attached should fix the problem with mem-free.

The attached also fixes another problem with Old World ROMs. In Open Firmware 1.0.5, the $find word would leave an extra item on the stack if the search doesn't succeed.

I haven't yet tried to flash it. I'll try that tomorrow. Can I use Windows 10 to flash it?
#25 doesn't work at all on my G5 Quad setup. No OFW screens or anything. Reverted to #24 and OFW screens work but with previously described Illegal memory access errors.
 

joevt

Contributor
Jun 21, 2012
6,699
4,089
Apparently not a lot…
I think that is the expected and correct output.

I tried a manual `probe-all` from the OFW prompt and it threw a memory error with the #24 ROM
That's fine. I don't think probe-all should be ran manually outside nvramrc.

#25 doesn't work at all on my G5 Quad setup. No OFW screens or anything. Reverted to #24 and OFW screens work but with previously described Illegal memory access errors.
I'll do more testing.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.