Sure, you can try overclocking your i7 7700. It's a common choice for performance gains. As for the Z170-Gaming K3 BIOS version F23a, make sure it supports overclocking before attempting. Whether it's worth it depends on your needs—better performance and stability are key factors.
Normal overclocking isn't possible for non-K CPUs. K series chips have their multiplier enabled, allowing gradual adjustments until stability problems arise, after which you balance voltage, temperature, frequency, and reliability. Non-K processors are fixed in this manner. BCLK overclocking is an alternative but limited; it won't push performance significantly and can affect connected devices like SATA controllers or Wi-Fi adapters, potentially causing instability. As mentioned, it's not recommended.
Yes, performance is capped around 103 before the system shuts down. On 6th generation and newer Intel chips, BCLK is divided into two parts: a PCIe clock for peripherals like SATA controllers and a reference clock for CPU and memory speeds. This separation means high BCLK doesn't impact components such as SATA controllers. By the 7th generation, running at 200MHz BCLK becomes feasible without major stability issues. The same applies to Z690/Z790, though I've noticed POST problems above 150MHz, marking that boundary.