At last, the final piece of the puzzle is finally complete. While I wanted to put an M-Audio Audiophile 2448 sound card in my MDD so I can hook it to my stereo system and listen to my music in full quality. The latest drivers for it was basically a piece of crap and caused Tiger to Kernel Panic. It worked as intended in Jaguar, so I ended up removing the card and get a Firewire version, which came out later.
With that, comes the Geforce 4 Ti 4600, which is a beast of a card in 2002. Sadly, finding such a card is difficult since it's sought after not because it was high end, but it's rare. I guess YouTubers who focus on retro computing gaming builds and Covid lockdowns are fueling the demand of old computer parts. After all, if you are stuck at home and want to build a nostalgic mid 90s, early 2000s gaming PC running Windows 98/2000, why not?
I manage to find a PC version for $200, which is a bit overpriced, but I just wanted it after trying to buy it from several used computer part shops that said to have stock, but in reality, they don't. This is a reference version of the Geforce 4 TI 4600, which has the same layout of the Mac version with the same reference cooler, except manufactured by PNY.

Flashing the card is a challenge since I have no PC with AGP. I decided to build a Pentium III retro gaming PC to run the games from the late 90s and early 2000s. Of course, it was not without challenge as I had problems getting parts that work. The first motherboard and CPU combo didn't work since the motherboard seems incompatible with the Pentium III (it only supports Pentium II despite using a 440BX).

So, I decided to avoid OEM motherboards and seek out a Intel SE440BX. The second try, I received the wrong motherboard, so that went back. Frustrated, I eventually paid a little more for a new old stock Intel SE440BX-2 and it worked. It was a challenge to get it to post, but I just needed to replace the CMOS battery and make sure the video card is seated. I had a PCI ATI Rage XL video card installed if the flashing process botches up and as a safety measure.
To flash the card, you need FreeDOS and NVFlash (provided in this post). You can use a SD to IDE adapter to do this as booting from flash drives aren't going to work on older computers. Just use Ruufus to install FreeDos and copy the SD card. After booting, you need to extract the ROM by typing the following:
C:\> nvflash.exe -b 4600.rom
Afterwards, shutdown the computer, take out the SD card and put it in a reader on a PowerPC Mac or a Mac running Snow Leopard. The
TI Rom Maker doesn't work on versions later than 10.6 since it needs Rosetta. Use the rom file you extracted with the TI Rom Maker and copy the modified rom back to the SD card. Then remove the SD card and put it back in the SD to IDE adapter.
Now run this command:
C:\> nvflash -4 -5 -6 <modifieldromfilename>.rom
When prompted, say yes. It should flash and once it's done, remove it and take the video card out of the PC and install it in the Mac.
After this process, it seems to work perfectly. Yes, it works with both displays. Of course, if you have any ATi drivers, you need to remove all the extensions and control panels or the computer won't boot properly.

While the performance is still bad in Sims 2, which is a later game, SimCity 4 was a slight improvement. Also, it scored up to 4x higher in OpenBenchmark over the 9000 Pro.

The final build:


Final Thoughts:
While this build wasn't cheap and I ended up wasting some money on parts I didn't use, it was pretty fun. I guess from this, which ended up with two retro computers to run old computer games and have all that nostalgia when I was a kid in the 90s and spent most of my childhood in front of a computer or playing video games. But back then, I was using low end Performas, which aren't really that fast and a budget Windows 98 PC running a 400 MHz AMD K6-2 with a low end ATI Rage Pro 3D graphics and no AGP port. Either way, these builds should last for a long time, barring if I find some more upgrades for a reasonable price.
Full Specs:
PowerMac G4 MDD (2003 Model)
1 GHz Dual PowerPC G4
2 GB of DDR RAM
NVidia Geforce 4 Ti 4600 video card
275 GB Crucial MX300 SSD (Mac OS X Tiger/Jaguar)
120 GB Samsung 840 EVO (Mac OS 9)
SSDs connected to a Firmtek Serialtek 1v4 PCI-X SATA Card
Apple Keyboard and Apple Mighty Mouse
Apple 24" LED Cinema Display connected to a DisplayPort to DVI active adapter.
Bose Companion 20 speakers.
Adaptec USB 2 PCI Card with NEC USB2 Controllers