This issue has been brought up before but not quite so I still don't have a clear answer for it. I have a Mac Pro 3,1 2xQuad 3.2Ghz and I like to upgrade its graphic card from nVidia GT 8800 to something that runs OK with Final Cut but I can rely on the future shift to Adobe AE / Pr because of time saving in effect rendering if I can take advantage of real time effects in mercury engine. It seems that nVidia Quadro 4000 works with Mac Pro 3,1 models. Also since it is a 2008 computer, nVidia GTX 285 that came out around the same time is compatible with it. I'm wondering if anyone has tested these two cards in parallel in Mac environment for Adobe mercury engine performance, especially with a harpertown (Mac Pro 3,1) processor. I imagine the operating system and computer processor would affect the performance of the graphic card and all the comparisons and reviews I read is either not mac or not adobe or does not specify the Mac model so I suspect it is in the newer generation of macs. It is additional 400 to 500 bucks investment to buy nVidia Quadro 4000 and if I can get away with nVidia GTX 285, it would be good especially if I know Mac environment and 3,1 architecture doesn't take full advantage of Quadro 4000. Is there anyone out there that tried these two cards under this circumstance?