I want to upgrade my computer with SLI, an additional SSD and Nvidia 3D vision 2. But i don't have any previous knowledge or experience about SLI, so i want to information or opinions on my possible future build. I plan to buy a Geforce 670 with reference cooler because it's a lot cheaper. So my main concern is the power supply and temperature, would also know if there is a possible downside to have a second card from another maker?
And i don't plan to overclock my CPU or GPU
Asus Saberthooth x79
I7-4930k 6-core 3.4 Ghz
16 GB Ram
Gigabyte 670 standard OC
Corsair AX 850 watt (3 years old)
2 TB WD hard drive
2 TB 7200 rpm WD hard drive
180 GB Intel SSD
Edit: i got a Asus 144hz 27 inch 3d display and psu is about 3 years old.
Main use is for gaming and gpu rendering in Blender.
There really is no downside to SLI. It's really stable and Nvidia does a great job with their driver support for SLI. It's solid technology.
To me, 3D is not as much of a big deal as the monitor you'll need to buy to run 3D. The monitor required will have a 120Hz+ refresh rate (most likely 144Hz). This means little perceivable tearing at the framerates two 670s can pump out. Also, these monitors have very fast response times (1 or 2 ms) minimizing perceivable blur and a very little input lag. All of these things are good for gaming in 2D.
Some games are fun in 3D. The Batman Arkham games are fun in 3D and so are most other 3rd-person type games. MMORPGs that support 3D are nice as well. First-person shooters seem a little off to me.
That AX850 PSU can easily support a system with two 670s.
You will have no problem using a second GTX 670 from another manufacturer as long as it has the same amount of RAM on it as the card you are currently using. If you're current 670 has 2GB of RAM, get another 670 with 2GB of RAM and you're good to go.