Overall, this is a solid build that should be able to handle most modern games and applications without any major bottlenecks. However, there are a few things to consider.
Firstly, the Ryzen 5 3600 and Zotac Gaming RTX 3070 are a good pairing. The Ryzen 5 3600 is a powerful 6-core, 12-thread processor that should handle gaming and multitasking with ease. The RTX 3070 is a high-end graphics card that offers excellent performance for gaming at 1440p or even 4K resolution. Together, they make for a great combination.
The 16GB of RAM at 3200MHz is also a good choice, as it provides a good balance between price and performance. However, it's worth noting that Ryzen processors tend to benefit from faster memory, so if you can afford it, going for 3600MHz RAM could provide a slight boost in performance.
The Gigabyte B450 motherboard is compatible with the Ryzen 5 3600, but it's important to check if it has the necessary BIOS update to support the Ryzen 3000 series out of the box. If not, you may need to update the BIOS before installing the processor.
As for storage, a 256GB SSD is a good starting point, but it may fill up quickly if you plan on installing a lot of games or applications. Consider adding a larger HDD or a higher capacity SSD for additional storage.
Lastly, the Corsair CV 650 80+ Bronze power supply should be sufficient to power this build, but it's always a good idea to double-check the power requirements of your components to ensure they are within the power supply's capacity.
Overall, this build should provide a great gaming experience, but it's always a good idea to double-check compatibility and consider any potential upgrades or adjustments based on your specific needs and budget.