Hi I can't find the cuda switch in my PowerMac g4 dual mirrored, What is the difference between resetting pram by keyborard or cuda?

First I need to caution you. The G4 MDD does NOT have a CUDA button like older Macs--it has a PMU reset button. The difference is that, for a computer with the PMU system like yours, you give the button ONLY one short push, no longer than one second.

If you treat it like it is a CUDA button and hold it for 20 seconds, you will seriously harm your computer. That said, this image shows the location of the PMU reset button in a G4 MDD:

What is the difference between resetting pram by keyboard or cuda?

As your G4 does not have CUDA reset capability, this becomes a moot point. In older Macs (Beige G3 and older--teh "Old World ROM" Macs) resetting PRAM via the keyboard did not fully zero everything; the CUDA reset did.

Hi, since it is starting in FW Target Disk Mode, it may be the video card... is the a floating FW synbol on the MDD's screen?

If so try booting the MDD in Safe Mode, holding SHIFT key at bootup.

See japamacs page here on the best AGP cards for G4s & G5s...

http://www.jcsenterprises.com/Japamacs_Page/Blog/4B4B7BA2-7ABB-47F1-87AC-B03D379 42BEE.html

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