Hey I'm Justin from Australia,
I recently purchased a nVIDIA Geforce 9600 GSO for my AMD 4800, i am now having the same problem that many people have. I have inserted the graphics card into the motherboard and the fan on the graphics card is spinning, once i connect my monitor to the graphics card it comes up on the screen with No Signal, (if i connect it to the plug and play graphics card the monitor works fine). I have tried downloading the drivers for the 9600 but it comes up with a error message.
If anyone has any ideas how to fix this problem it would be greatly appreciated.