Setting up - definitely NOT a nightmare. In fact, as long as the power supply and motherboard are certified SLI-ready, and the SLI bridge ribbon/connector (comes with an SLI-certified motherboard) and an additional two PCI-E power connectors (comes with the SLI-certified power supply) are handy, it's a simple install. Because I was coming from a system that already had a single 670, drivers were all loaded, and nothing needed to happen in BIOS or anything. The only minor confusion is there's two connectors to hook the bridge up, but only one bridge is need in a dual-GPU setup. I took a guess and picked one, googled this dilemma, and found out both connectors are identical and either one is fine. The reason for two connectors is for 3 and 4-way setups.
So after trying some games that push my system, I'm left with mixed feelings.First the good:
My 670s are the Gigabyte Windforce 2X OC Edition
. I was concerned that two of these in my computer might noticably raise the noise level, but I can barely tell the different between running one or two of these - the are very quiet cards.
I ran the Catzilla benchmark and my system's score is now around 70% better. Which is impressive because CPU seems to be factored strongly in this test.
I loaded up Far Cry 3 set everything to ultra, and it ran smooth and looked great in the process. The single 670 couldn't handle this level of graphics. Crysis 2 also seemed to have no problem with framerate on Ultra, although I noticed some graphical oddities that I didn't notice with my dialed-down setup. This can probably be fixed with adjusting one of graphics options, or some nVidia control panel tweaking.Then the bad:
...or at least not "bad", but somewhat disappointing - it didn't do everything I had hoped. But that had more to do with expectations and understanding the limits and problems of certain software.
A couple examples - I was hoping SLI would fix some problems I was having in a few areas of Borderlands 2 where the framerate would drop to the 40s and sometimes 30s. After more testing in SLI, I found these drops are because certain sections aren't optimized for PhysX, at least with the current Nvidia drivers.
Also, I loaded up Batman: Arkham City and put everything on Ultra - no good. Traveling around the open city has inconsistent framerates, and some areas of painful slowdowns. Again, I believe this is more software optimization, and not anything wrong with the computer's setup.Overall:
My target for games is 1080p at solid 60fps with no drops. I hoped that doubling my GPUs would help with headroom with certain games that didn't live up to my target, and it did very well with the Crytech games. But other games that had trouble spots, SLI seems to make little to no impact over a single 670. At least in early 2013.
At higher resolutions beyond 1080p, SLI would have a greater value, but for those targeting 1080p @ 60fps, a single 670 is fine for most of the games out there. Even with SLI, there certain unoptimized games where settings have to be dialed down.
But it's good to know I don't have to worry if my system is underpowered for the next year or so. Edited by DaverJ - 3/2/13 at 10:46am