Go for the Quadro 4000 if one of the following is true:
- You have a HP Dreamcolor (€ 1800) 10 bit monitor or better and NEED 10 bit output.
- You don't care for lesser performance and you have deep pockets.
- You want bragging rights no matter what is costs.
Go for the GTX 670 if one of the following is true:
- You don't need 10 bit output.
- You want the best performance for a reasonable amount of money. The best BFTB (bang-for-the-buck).
- You may want to attach more than three monitors at some time.
Recently a € 3900 Quadro 6000 demonstrated that it does not perform any better than a € 237 GTX 470. The Quadro 4000 is far less than a 6000.
Moved to Hardware forum
To the Quadro 4000's benefit, it's a single slot card, requires less PSU wattage and if you are considering 3D animation software, enhances viewport redraw. On average, the higher cost is definitely a factor against it. Although mine was (literally) a $2 upgrade over the standard GPU when I ordered my Dell T5500 awhile back. Now with CS6 I'm able to use my second screen as a large program monitor while also having A/V go out via firewire to a VTR at the same time(with MPE on) in addition to source, program and 'scopes present on my main screen. I'm pretty sure that this enhancement is not limited to Quadros, but it does work for me.
BTW, having an extra available card slot could come in handy for a Fusionio ioFX board for AE! ;-)
I haven't really been keeping up with the GTX 6xx series cards as of yet, but from what I can see, the GTX 670 should handily outperform my GTX 570. I bring that up because I pulled the Quadro 4000 out of my Mac and replaced it with the GTX 570. Exports using the MPE in hardware mode took, literally, half the time.
I can only assume the same would apply to the PC; I see no reason why it wouldn't.