This reminds me of the time I had to do very similar work to get SLI GTX 285's to function on a Hackintosh. I couldn't find anyone that had done it before at the time, and had to author my own kexts to get it to work. Spent 15+ hours over a long weekend, and eventually somehow managed to get my tri-monitor rig functioning.
I still vividly remember when I rebooted for what felt like the millionth time, and I saw the familiar grey screen only on my center monitor, once again facing defeat... and then - as the OS flashed blue before loading the desktop - all three monitors lit up in a sea of aquamarine, before revealing my wallpaper and windows spread across all three screens.
To this day, it's one of my most favorite moments with respect to computers and building as a hobby.
Drip, drip, drip...
Dashes of salt are still warranted, but these numbers do make sense when put next to the limited gaming benchmarks that NVIDIA themselves have shared. Their website shows 1.6-1.8x improvement (when comparing stock 980 to stock 1080) for "traditional", non-VR gaming. And, doing the quick math:
LEAKED (UNCONFIRMED) 3DMARK SCORES
980: 13148
980 Ti: 17042
1080: 21828
1080@2.1: 26456
1080 vs 980: (21828-13148) / 13148 = 1.66x improvement
That's not really >= 980 SLI, but it's pretty close - I'd put a 980 SLI setup at around 1.7-1.8x a sole 980, when accounting for the inefficiencies of SLI.
More interesting, and more exciting, is that OC benchmark, given that NVIDIA got to 2.1Ghz on their reference cooler in their demonstration. We won't know how reliable you can hit that until we see lots of reviews, and this is doubly the case for cards that don't use the Founders Edition shroud. But NVIDIA was conservative if anything when they discussed Maxwell's OC-ability, so there's certainly the potential that most folks could get to 2.1 with relatively little effort. Plus, more performance-oriented coolers will only lift the thermal ceiling higher (though, as with Maxwell, that might not even be what limits overclocking in the end).
1080@2.1 vs 980: (26456-13148)/13148 = 2.01x improvement
Now that's beating a 980 SLI any day of the week.
