With the GeForce GTX 1660, NVIDIA is clearly attacking AMD's Radeon RX 590 offering. The GTX 1660 is based on the same TU116 graphics processor we saw on the GTX 1660 Ti not long ago. Besides shader count and clock frequencies, the biggest difference between both cards is certainly that the GTX 1660 uses GDDR5 memory whereas the GTX 1660 Ti uses GDDR6. Unlike other Turing GPUs, TU116 does not feature acceleration for RTX real-time raytracing or DLSS because the specialized hardware consumes a significant portion of the die area on other Turing GPUs, which increases manufacturing cost significantly. NVIDIA did keep the other improvements of Turing though, like larger caches, concurrent execution of float and integer operations, and adaptive/variable rate shading.

As a result, when averaged over all our gaming benchmarks at 1080p, we see the Zotac GTX 1660 TwinFan beat AMD's Radeon RX 590 by a solid 10% margin. The GeForce GTX 1660 Ti and last generation's GTX 1070 are 13% faster. With 20% higher performance than the GeForce GTX 1060 6 GB, at slightly higher pricing, the GTX 1660 is in a position to conclusively replace the GTX 1060 easily. Zotac didn't overclock their card out of the box, something that's reserved for their higher SKUs. If you compare the framerates to other factory overclocked GTX 1660 cards tested today, you'll see that the differences are really small and barely matter. With those performance results, the GTX 1660 is a good choice for gamers running high details with a 1080p Full HD monitor. Compared to the GTX 1660 Ti, you do have to sacrifice a few settings to reach 60 FPS, but you'll save good money while doing so.

Zotac's GTX 1660 comes in a highly compact form factor, using two fans with a dual-slot cooler. Such a compact cooler of course puts constraints on cooling performance, yet temperature are still low with only 68°C. Unfortunately, Zotac didn't include the highly popular idle-fan-off feature, which turns off the fans completely during idle, Internet browsing, or light gaming. In gaming, the card is quiet, but I would have liked it to be a bit quieter still. I can see why Zotac went for these fan settings, though; they probably sought to hit temperatures below 70°C. The inclusion of a backplate would have been a nice treat, even if it were just a plastic backplate like on the MSI Ventus XS. It would have improved the overall look and feel of the product significantly.

Compared to Pascal, Turing improved power efficiency once more, and the GTX 1660 is no exception. Zotac's GTX 1660 uses only 108 W during gaming, which is even more impressive when you consider how much gaming performance the card has in it. Even compared to the latest Turing RTX GPUs, the GTX 1660 achieves 10% better performance per watt. Against AMD's Radeon RX 590, which was just recently released and uses a 12 nm production process as well, the GTX 1660 is 2.5x more power-efficient; that's 250%!

Our manual overclocking yielded substantial performance improvements that brought the card performance levels which beat the GTX 1660 Ti. Surprisingly, GDDR5 memory overclocking didn't work as well on the Zotac card as on the other cards reviewed today. While competitors hit a wall at 2500 MHz, Zotac's Twin Fan "only" achieved 2400 MHz, which is still an impressive 20% memory overclock. GPU overclocking, on the other hand, reached results similar to other cards tested today.

The lack of ray-tracing and DLSS on GTX 1660 and GTX 1660 Ti seems like a big deal at first, especially considering how much NVIDIA is promoting those technologies. While both are extremely promising, they are not the most important things to have right now, especially in a market where every dollar matters. While I have no doubt that RTX support will be growing vastly, only a few titles support it at this time, so I don't think anyone could be blamed for skipping the tech for now and waiting for it to mature more. Looking at silicon economics, including RTX/DLSS would have either driven die size (= cost) so high that reaching the targeted price point wouldn't be possible anymore, or the number of shader cores would have had to be reduced, which would have resulted in no performance improvement over AMD—NVIDIA went the other route. "RTX" is actually a great vehicle for NVIDIA to sell a feature that is more than just "higher FPS". This card specifically targets people who are comfortable with 1080p 60 FPS and won't even mind playing at lower details as long as their GPU is affordable. If, however, they feel they miss out on visuals, something DX12 couldn't achieve, they might be tempted to spend more and go for the RTX 2060, for example. The next step for NVIDIA is transitioning to the 7 nm production process, which increases density and should allow smaller GPUs to have RTX, too.

Zotac's GTX 1660 TwinFan comes at NVIDIA MSRP of $219, which is excellent and ensures the card's strong position for the budget-minded buyers. It looks like the aging GTX 1060 6 GB has finally found a worthy successor. The GTX 1660 offers better performance and efficiency at a similar price point—NVIDIA will sell millions of these. AMD's Radeon RX 590 will be a tough sale now. The GTX 1660 is faster, cooler, quieter, and cheaper. The only win for the RX 590 is that it comes with a strong three-game bundle, which could offset your cost significantly. NVIDIA doesn't bundle any games with the GTX 1660. I have no doubt that AMD will quickly adjust their pricing to address the changed market conditions. Radeon RX 570 and RX 580 have already seen price drops, down to $130 and $170, respectively. Especially the RX 570 is now at a price point so low that many people are going to be willing to overlook its shortcomings in both performance and noise, and the two-out-of-three game bundle will help here, too.