Yes, with regards to performance, Nvidia GeForce GTX 1660 SUPER outperforms, GeForce GTX 980 Ti by 4.9%.
The GTX 1660 SUPER is more energy-efficient considering its peformance, consuming 125 watts to produce 3DMark score of 6078. By comparing its benchmark score to its power consumption, we get an efficiency score of 48.6. GTX 980 Ti's efficiency score is 23.2, 109.9% lower, making GTX 1660 SUPER the smarter choice in terms of power consumption.
When considering value for money, GTX 1660 SUPER offers a better deal than, GeForce GTX 980 Ti by 164.3%. Here is more in depth overview of the price and used prices of GTX 1660 SUPER Price History and GTX 980 Ti Price History