The 1650 has just 896 CUDA cores versus 1,408 in the base 1660, a 128-bit memory bus instead of a 192-bit bus, and 4GB of GDDR5 memory in place of 6GB. It's also clocked slightly lower at 1,485MHz base compared to the 1660's 1,530MHz, and a 1,665MHz boost clock instead of 1,785MHz. You won't be using this for 4K gaming any time soon as a result. However, it could still represent giant strides ahead of NVIDIA's past GPUs. The company claims that it's up to 70 percent faster than the GTX 1050 at 1080p, and twice as fast as the aging GTX 950. So long as the real-world performance comes reasonably close, it could be a viable upgrade if you're mostly interested in keeping pace with modern gaming than maxing out the resolution or visual quality.
The 1650 is immediately available through third parties like EVGA. Not surprisingly, there's no NVIDIA-made reference model. Whether or not it's a smart buy is a tougher call. It's currently priced around the same level as AMD's Radeon RX 570, which could give it an edge simply by using a considerably newer architecture (AMD has yet to use Vega in this GPU price class). We haven't seen how cut-down Turing hardware fares against the competition as of this writing, though, and AMD may still have a few advantages like its 256-bit memory bandwidth.