This page is a wiki. Please login or create an account to begin editing.

7800GTX ROMs for PowerMac G5

Your rating: None Average: 5 (1 vote)
Year released:
[www].se [ftp].se [mirror].us [mirror].de (30.18 KB)
MD5: 6191c3935f4f61b9c26669475228ea35
For Mac OS X
[www].se [ftp].se [mirror].us [mirror].de (30.13 KB)
MD5: 10eafddc5c97107bc6946926c613f7e3
For Mac OS X
Guides on emulating older applications

Throughout the early 2000's, many Mac experts & enthusiasts have found ways to hack graphics cards that were designed otherwise to work in their Macs. This is one of those.
This is a modified ROM file that allows you to use an NVidia 7800GTX on the PCIe enabled Late 2005 PowerMac G5. This card is said to be 10 to 20% (depending on game or application) faster then the fastest OEM G5 card, the Quadro FX 4500. Benchmarks can be seen here.

The first download is believed to be the original rom (not entirely confirmed). This is the recommended download.
The second download is a modified version created by MacRumors forums user rabidz7. It has been criticized by some as having the wrong clock rates and being unstable.

see also: X1950XT ROMs for G5

Architecture: PPC

Requires a Late 2005 PowerMac G5 Quad/Dual Core (not Dual Processor) and a 7800GTX (512mb version) card.

The flashing process must be performed on a PC (unfortunately).


pc297's picture
by pc297 - 2021, January 29 - 12:10am

I can confirm that the first ROM ( works well. One has to use nvflash 5.13 though as later versions don't support PPC roms. Be sure to back up your original ROM though! I used the following commands:

nvflash -b backup.ROM
nvflash -4 -5 -6 7800_GTX_512.ROM

Here are the frequencies I could read from the performance table:


100% fan speed
1.45V core voltage
545 Mhz core frequency
825 Mhz memory frequency (x2=1650Mhz DDR)

Very close to the PC specs (550 Mhz core and 2x850 Mhz memory)

I haven't tried or checked out the ROM from rabidz7.


Do you mean the ROM from japamac? I never could get ahold of that one, the link on MacRumors that he posted is dead... Do you have it by any chance? He usually makes really well optimised ROMs, would love to get it!

Re the 256Mb version, I think Luigiburdo has it flashed for ppc mac in his radeon HD 6570 + GTX 7800 G5 rig, so he must have the ROM somewhere. On this note I could get a radeon HD 5770 to work in a G5 Quad under Lubuntu 14.04 but never under newer versions (of it and of Mate for that matter) with his instructions. Pretty cool to get to work though!


Jatoba's picture
by Jatoba - 2019, April 25 - 11:52am

The rabidz image might as well be removed, it is non-functonal and the user as a whole is very untrustworthy. The first download doesn't sound good, either, when all it offers is the original ROM and even THAT it is not certain of.

There is a quality ROM for G5 usage that was provided by another user at MacRumors, and that one was tested by many. They all said it worked perfectly, no exceptions. I lack that GPU, so I can't tell. Sad

By the way, all the hacked ROMs I came across were for the 512MB VRAM version of the 7800GTX. There's a far more easily found version of this GPU, but one that is inferior, mostly for having only 256MB VRAM instead, which I never saw a flashed ROM for.

By the way, if anyone is willing to sell me their 7800GTX 512MB VRAM version, I'm interested. Wink

Oh, also, someone also on MacRumors stated the 256MB VRAM version of the ATI X1950XT performed even better (higher clock?) than the 512MB 7800GTX in real tests. I'm not sure if that's true, but I can help others compare, since I have that card successfully flashed. Smile (P.S.: That card once flashed works mostly only with Leopard, with the ROM that circulated.)