Yes, Nvidia is where i would go. However, the hack on the newer GTX 5-series only works on post 2008 machines. The gtx 285, Quadro 4000, and i believe the GT120.
4,1 would be about 2008 so i would check to see if that fit.
You know I tried the hack for the GTX570 on my 2,1 and there was no go so i have it sitting here waiting for the mac pro update so i can get this card in. Sadly i am using AE and PP without cuda. ( not bad but no bells and whistles either )
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What you do with what you have, is more important than what you could do, with what you don't have."
> > > Knowledge + Action = Wisdom - J. Corbett 1992 """"