Addendum
I've kept track of a few other attempts to do this flash and wanted to add a bit of knowledge I've gained from hearing about other people's experience.
- Device IDs
First off, the DOS program used to flash the card in the PC (nvflash) can give you some crucial bits of information that will make the flash successful. RivaTuner is also useful here. The most paramount pieces of info are the two device IDs (DIDs). Each video card has a device ID stored in its ROM and another device ID hardwired into the card. On the PC these two IDs can be different, but when flashing the card you MUST make them match for the card to work in the Mac. This is accomplished by the following procedure:
Put the card in a PC and use either nvflash (command list
here) or Riva Tuner to check the hardwired DID. Then use a hex editor to change the DID in the ROM to match the hardwired DID. These two MUST match for the card to work in the Mac.
Also note that it is not always necessary to hex edit the ROM, since sometimes the hardwired DID matches the DID in the Strangedogs ROM. In my case, they did match right off the bat and no hex editing was needed. However others with the same card have had to do so, therefore it is a must to check the IDs before flashing. This is made more important due to the fact that the command suffixes used when performing the flash override any device mismatch so you won't know if there is a problem unless you check.
- Test in the PC before flashing
Another issue which bears mention - once you recieve your new card for flashing the FIRST thing you should do is to slap it in the PC and run 3DMark or other intensive benchmarking apps for a significant period of time. Stress that card out. This will give you a chance to look for screen artifacts (which indicate a defective card) and ensure that the heatsink/fan are doing their job. If the card runs too hot in the PC, or has artifacts, you should return it and get another one. This would also be a good time to experiment with overclocking the card, if you are planning to do that in the Mac. It might not like to be overclocked much, and now is the best time to find that out.
- New Low-Voltage ROM
I flashed my 6800GS->GT with Strangedogs' "2120m" ROM. Since then they have released a ROM file that runs the card at a lower voltage. This new ROM, the "2121m", should lower temps and improve the lifespan of the card. I recommend using it.
One more thing - Strangedogs has recently developed flashing procedures for three new AGP nVidia GeForce cards. These are the
6600GT,
7800GS(!), and
6200. The 6200 is especially great because it fits in the Cube, has dual DVI, can run new apps like aperture, AND runs cool even without a fan! Definitely something for serious Cube users to look at. All three (and probably every new card from now on) require that a new 128k ROM chip be soldered on to replace the 64k unit that all cards ship with these days. All three cards, when modded, should work in AGP G5s and most, if not all, G4 towers. They have also gotten several PCI-e cards flashed successfully (off the top of my head I belive they include the 7800GT and 6600GT).
