Hello! Based on your setup, both the Intel Core i7-7700 and the Intel Core i5-10400 are capable processors. However, if I were to choose between the two, I would recommend going for the i5-10400. Here's why:
1. Price - The i5-10400 is more affordable than the i7-7700.
2. Performance - The i5-10400 has a higher base clock speed and turbo boost frequency, which means better overall performance.
3. Future-proofing - The i5-10400 is a newer processor that has support for DDR4 RAM, which is more future-proof than the DDR3 RAM that the i7-7700 supports. Additionally, the i5-10400 is compatible with newer motherboards, which means you have more upgrade options in the future.
Overall, both processors are capable, but the i5-10400 is more cost-effective and more future-proof. Just make sure to get a motherboard that is compatible with the i5-10400 and your 1660 Super graphics card. I hope this helps!