Hardware Canucks tried the The NVIDIA GTX 980 SLI
A quote from the article:
Here we are almost two weeks after NVIDIA's GTX 980 and GTX 970 launched and interest hasn't diminished in any way. With that being said, the availability situation has somewhat improved so these cards are getting into people's hands after initial bout of utterly insufficient allocation. All in all things couldn't be going better for NVIDIA's Maxwell architecture so there's no better time to start looking at how things are looking when they?re placed in an SLI configuration.The NVIDIA GTX 980 SLI Review @ Hardware Canucks
The GTX 980 will be the first card out of our multi GPU testing gates simply because we have two reference samples on hand (remember, the GTX 970 doesn't have a ?reference design? per se) and it's vying for top-dog status in a pretty competitive segment. To refresh your memory, in a single card configuration it can handily beat the R9 290X and usually remain ahead of NVIDIA's own GTX 780 Ti despite costing just $549.