Graphics Cards for MacPro

What is the best and most effecient graphics cards for a MacPro for DaVinci Resolve?

Currently I'm running a Mac Pro 2010 8x3.0Xenon with ATi Radeon HD 5770

From what I've read in the manual for resolve 9, a good graphics card for the price is the Nvidia GTX 570 2.5 GB edition they go for about 320.00 dollars online. A few notes to consider is that it is a two lane card so you would have to take your 5770 out and you will need to have Mountain Lion installed. On top of all that you will most likely need to have another single lane card installed in one of your other pci lanes that is supported by the os out of the box and hook up your monitor(s) to thatl

The PC Version GTX570 2,5 gb is just fine. Use the GT120 as your GUI card.

Would be interesting if something like the Quadro 2000D PC Version can be used as the GUI card in the MacPro next to a GTX 570. Looks like the Q2000D dont need a power cable. It operates at 62W. Does anyone know this?

S.

... is the Nvidia GTX 570 2.5 GB edition..

I read about 550 Watt power consumption. Is that true, will that still work in a MacPro?
Actually I am running a GTX 285 and a ATI 5770. With the GTX 570 I would have to replace
the 5770 for another card for the GUI. Which one would you recommend?
Thanks for your time!

pc cards run at half bus speed and do not show boot screen on mac.

Look for Macvids on ebay. They make mac compatible versions of pc cards and give great support imo.