Passar två GTX 690 till mitt moderkort?

In looking at the prices and with the knowledge that the gaming card is faster to render a scene than the Quadro 5000 or the Tesla 2050 the obvious question then becomes: How can anyone justify the huge cost difference of the Tesla & Quadro cards vs. the 400 series FERMI based “gaming cards”?
Answer: The main consideration (for me) is memory limitations of the GTX type cards. The Quadro & Tesla series house more on-board memory therefore I can render larger/more complex scenes. Of course I do have to say that it’s still difficult to fit complex scenes on the 3GB of RAM of the Tesla 2050 but it’s a lot easier than trying to fit a scene onto a 1gb GPU like my GTX 470. On the upside you can find some GTX cards with up to 2gb of on-board memory so I’d definitely look into those over the 1gb models if you plan on rendering with the card.
The other issue to consider is heat. I can tell you that my GTX 470 generates WAAAAY more heat when rendering than the Tesla 2050 or Quadro 5000. I do worry about that damaging the GTX card as I’m sure it wasn’t designed for this kind of abuse. I could water cool it, but to be perfectly honest since these gaming cards are common, somewhat inexpensive, and updated/redesigned frequently I would probably replace it within a year or so anyway. So if it lasts that long I’m good to go. The Quadro & Tesla cards are built to last longer under the stress of rendering. So your investment in a Tesla or Quadro card should last longer in that aspect.
NOTE: Seriously, if you render with GTX/gaming cards please make sure you have ample cooling and/or the workstation isn’t near anything flamable! I’m not saying they will instantly burst into flames when you hit the “make pretty button” but these things get CRAZY hot when rendering for long periods so please be aware of that.
The final consideration for me is 3ds Max viewport performance. In this aspect the GTX 470 pales in comparison to either the Quadro 5000 or the Tesla 2050. Don’t get me wrong, my 3ds max viewport performance isn’t bad with my GTX 470 but it’s noticeably more responsive/smooth with either the Quadro or Tesla cards.
Bottom Line: Which GPU(s) should you purchase? All I can offer on that question is advice on what I’d do. I do like the Quadro 5000 and Tesla 2050 because they are quieter & run cooler than the GTX card and of course I can render larger scenes with the Quadro/Tesla cards. That being said if I were building a new machine I would probably start with 1 GTX (FERMI based) video card with 2gb of on-board memory depending on the reviews of those cards. If the reviews didn’t look good for those cards I would start with a 1.5gb FERMI based gaming card. Try that with 3ds Max to see if most of your scenes fit into that 2gb of on-board memory. If most of your scenes do render with a 1.5gb or 2gb GTX type card then buy one or two more & enjoy some very quick rendering (but lot’s of heat). Just don’t be surprised if the gaming cards don’t hold up under the extreme stress of long periods of rendering, unless you water cool them.
If most of your scenes don’t fit onto the 1.5/2.0 gb GPU’s THEN you should explore the Quadro/Tesla series…OR wait & hope for someone to develop a GTX based video card with a lot of on-board memory. The other option is a Tesla 2070 that has 6GB of on-board memory. It would be awesome to have two or three of those! However that configuration would be really expensive but it might pay for itself if you can turn projects around quickly with that configuration.