Best answer: If you're building a new gaming PC or are upgrading from an older GPU, the NVIDIA RTX 2060 offers better value than the GTX 1660 Ti if you can stretch the budget a little further.
Better GPU for gaming: NVIDIA RTX 2060 ($350)
Well worth the additional funds
The RTX 2060 is more expensive than the GTX 1660 Ti, but it's well worth spending more than you initially wanted to. Why we'd recommend this is the RTX 2060 offers more performance for the money and would hold up longer over time before needing to be replaced. With the GTX 1660 Ti, you're likely to replace it sometime in the future if you wish to move up to 1440p and 4K gaming.
While the GTX 1660 Ti is capable of 1440p gaming, it's not as powerful as the GTX 1070 (though it does match it in some games), which itself can sometimes struggle with more demanding games at this resolution. The RTX 2060 makes mine meat of games and it costs less than $100 for all this additional headroom. You also have ray tracing and Deep Learning Super Sampling (DLSS) enabled on the card.
Other advantages the RTX 2060 has over the GTX 1660 Ti include increased memory bandwidth. It's simply better in every way aside from the base and boost clock speeds, but you can overcome with this overclocking as RTX 2060 cards come with superior coolers.
We'd recommend the RTX 2060 over the GTX 1660 Ti, but it's not the best option for everyone. If your budget simply cannot stretch to cover the GPU and you need the card now, the GTX 1660 Ti is a solid card for 1080p and some 1440p gaming.
If you want a deeper dive on the differences between these two graphics cards, you can check out our comparison.
Our pick
ZOTAC Gaming RTX 2060
Better value GPU for gaming
The GTX 1070 was a great mid-range GPU and the RTX 2060 is the spiritual successor with a few additional features, including ray tracing and NVIDIA DLSS. You'll be able to play PC games at 1440p without issues.