Hardware Canucks tried the The NVIDIA GTX 980Ti Performance
A quote from the article:
When NVIDIA launched their TITAN X, everyone knew the GTX 980 Ti wouldn't be too far behind. Based on the same GM200 core as its bigger brother, this new card is meant to lead a more affordable (yes, you read that right) lineup into the DX12 era while also preempting the upcoming launch of AMD's Fiji architecture.The NVIDIA GTX 980Ti Performance Review @ Hardware Canucks
For the last two generations, the cadence of NVIDIA's product lineup has followed a lock-step approach and this time is no different except for a few points. The last high end Ti-series card was the GTX 780 Ti, a product launched in response to AMD's extremely competitive R9 290X. It was able to pull away from the Radeon lineup's darling while also consuming less power and providing a substantially quieter gaming experience.
The situation this time around, almost 19 months later, is significantly different. Other than the R9 295X2, AMD has failed to launch any product refreshes that put pressure on NVIDIA's high end Maxwell cards. As a result the GTX 980 and subsequent GM200-based TITAN X found themselves all alone, competing against the nearly two year old R9 290X. Nonetheless, the GTX 980 Ti is still being rolled out as NVIDIA keeps marching lock-step with their roadmap regardless of what AMD does.