Hey this card Works! 

It didn't at first, but that turned out to be a driver issue. Even though I have 9.2.2 installed it was still running the 2.4 Nvidia drivers. I updated it to 3.5.2 and it fired right up using the DVI connection.

HOWEVER! Here is where it gets weird.

I connected my second DVI monitor to the ADC port using the Formac ADC to DVI adapter and for no apparent reason the G4 wont even turn on, no lights nothing. I had to disconnect the ADC adapter and leave the G4 unplugged for 5 minutes and then reconnect power (without the ADC connection) to get it to turn on.

What the heck is that all about?

So it looks like a common problem where the G4 will not power on when using the ADC connection unless you are using an ADC monitor, I can plug the ADC to DVI adapter into the mac while it is running and it turns off. Seems to be looking for a voltage.

I am reading through the following blog covering the topic, hopefully there is an answer in thee somewhere. http://hints.macworld.com/article.php?story=2005040811124189