Setting up SLI - a "nightmare"?

I decided to add a second GTX670 to my rig for a little dual-GPU SLI action. But every time I read about SLI, I also read the words "problems", "headaches" and "not optimized" associated with this task.

I want my computer to be as trouble-free as possible, so I have to ask: Is adding a second GPU really like entering one of Dante's Circles of Hell?

For the record, I understand two 670s might be foolish overkill for the most part these days, but I won't rest until I experience it.

UPDATE: click here for my experience.
Edited by DaverJ - 3/2/13 at 9:31am

Cool, thanks guys. I ordered an identical 670, and my power supply is a SeaSonic 750 watt, so I should be good.

It'll probably happen tomorrow, so I'll post back here with results and findings.

Thanks for the heads up, and that wasn't insulting at all.

I think nVidia should mandate the SLI cable should be included with every GTX card. It would put the option in the mind of everyone who buys a single card. I guess the downside would be the motherboard has to be SLI compatible, which definitely isn't a given, so there's potential for customer support "nightmare".

Anyway, I have my motherboard's SLI cable and power supply's dual 6-pin connector ready.

Will it work on Gigabyte cards?

Have you done your taxes yet? That's what did it for me.

So... SLI.

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

Yeah, through the "GeForce Experience" software, which updated to GeForce 314.07, dated 2/18/2013. I don't mess with the beta drivers anymore.

Nah, I'm probably happier with my dual-GPU setup than I seemed in that earlier post.

I was just disappointed to find buggy and/or unoptimized software still exists, no matter how much money and tech we try to throw at it. Being in console-land for so long, I had forgotten the efforts needed to run the occasional PC game. It's gotten better with automatic updates to drivers and optimal settings via "GeForce Experience" and patches via Steam, and many if not most games are trouble-free.

Even though there's still some room for improvement for gaming on the PC side, I'm not looking to jump back to consoles any time soon.