I am building a new rig that will be specced to do a medium amount of video/photo rendering & compositing as well as a medium focus on gaming.
Not familiar with these software, but from I heard is that if you are doing productivity stuff, always go for Nvidia. I would actually recommend a Titan here for the ECC stuff if you don't intend to add a Quadro in the future.
Blender is not quite there yet on opencl, if you want the best performance on blender you should get nvidia, 2 780's especieally if you can find the asus strix with 6 gb of vram, 2 980s would be good as well, but (a big BUT):
Blender cares a lot about fully desing chips, the 780 and titan have fully enabled gk110 chips while the 980 has the future second tier chip the gm204, when they get to release the second maxell generation, the chip will be the gm210, and It will be the titan and (let's say) gtx 1080...
it happened the same on the kepler release, the 600 series dissapointed everybody because the 580 was faster than the 670 and eveen 680, new optimizations had solve this a bit, but the 780ti rocks everything and if you can get 2 780 strix (the ones with 6gb) you'll have basicalle a cheaper titan with no compromises in rendering performance, becuase cycle's reverse pathtracing (the method of rendering in blender's cycles rendering engine) cares about the fp32 (not double precision or fp64) coun, memory bus (384 bit the kepler, 256 the maxwell) and rops (that's the only one that the maxwell is better than the kepler)
http://blenderartists.org/forum/showthread.php?350975-The-new-Cycles-GPU-2-72-Benchmark
here you have the benchmarks of the actual situation in blender... it may vary over next versions of the software
good luck!
the good news for you is taht you don't need SLI in blender, it takes advantage of different cards, you can see a lot of people in the link using different models, it just loads the whole scene to each gpu, and then ech gpu renders the blocks (tiles) that they are assigned to render. The downside is that your ram limit will be the lowest vram available, i.e. yo have a 3 gb ram gpu and a 4 gb gpu,, your limit ram isn't 7, it's 3, so take in considaration of getting enought vram for your project, but if you say blender it's not used that much I doubt you'll need more than 4gb of vram for now, in the future you might considering geting moar gpus with more ram, but for now you'll be ok, don't worry about sli, it's just for gaming, not for production (at least I can't recall a software that does take advantage of that).
and for redrocket or quadro, and firepro, today's gaming gpus have enough potential to be used unless fp64 (double precision computing) is needed, like fluid simulation or engineering, if you're not into that... maybe not worth it
By gm210 do you mean gm200? Since that is the chip the Titan II or 980 Ti will be using. Also, I didn't think 8gb 980s has been confirmed - but I might be wrong on that.
Finall, I wouldn't hold your breath for a new dual gpu card from nvidia. The last one was the Titan z and was available for the low low price of $3000
Why should he "allways" go for Nvidia wenn productivity?
If the software he is using can utilize open CL and Open GL, then a 290X would be obvious the better choice imo.
GTX9xx series for rendering? and what about the bandwith bus limitation of those cards? And the cutted amount of cuda core's? GTX980´s are indeed the best single gpu´s out there for gaming, but for productiviy i dont think so.
If you are mainaly gonne do rendering on the CPU, then the GPU isnt going to matter very much. In this case you could offcourse choose for the best single GPU GTX980 for your gaming performance.
But yeah a dual GTX970 or dual 290X for a few bucks more, will offcourse perform allot better at 1440p, in games that are realy good optimized to work with crossfire or Sli.
well I assume the gm 210 because that's what the nomenclature that nvidia has been using, but the gm200 as far as I know its not confirmed to be the titan 2 chip, yet, only rumours, so we should take it with a grain of salt... still I could be wrong, of course
because of his software options use cuda at the moment, when they get to opencl 2.0 I will be the first one to jum to AMD...
ya okay, blender is Cuda.
But adobe has allready implanted open CL / open GL support as far as i know. But Blender is indeed cuda. Still i thinkt that the current GTX9xx series cards are not the greatest for cuda rendering if you ask me. Simply due the lack of bandwith and cuda cores.
But i could be wrong offcourse.
i think that the older GTX780 6GB series are better at this. Or a Titan black offcourse.
of course they arent, my recommendation here is the 6gb 780, the fully enabled gm200 or 210 (really I dont't care the name) it's not there yet, but if they maintain the improvements of maxwell it could be awsome
yeah would be realy nice if the the gm200 gets fully onlocked.
Anyhow still if you realy gonne do serious cuda rendering stuff, i think you should go quadro.
But like i said with a 5960X you could also use the cpu to render on, Because that particular cpu is born for those kind of heavy duty workloads. So in that case, i think the gpu will make less sense.