Yes 600watts should be fine , we are not worried about wattage but more about quality of that EVGA W1 psu.This is just not the case. 600W is perfectly capable of running the parts they listed
Don't think a 9600K is a bottleneck for a 2070s.Think of your bottleneck this way.
Two weaker guys working PERFECTLY together will almost always beat a guy who is really strong but has a weak partner that he has to constantly worry about and try to carry in said fight.
That's what your system is doing. Your CPU was paired perfectly with the 1060 but now your CPU is weak compared to your 2070 Super, so your 2070 S has to constantly wait on your CPU to catch up to it, making it frustrated and refusing to perform as well as it can (in a humorous sense). Basically upgrade your CPU. Personally if you wanted to keep Intel, I'd go with at least a 10th or 11th gen i7, or possibly a higher-end 11th gen i5. Even then depending on your games and workload and game settings you may run into issues. The 2070 Super is a pretty beefy card and your 9600k is kind of average.
@Paul-Smenis , what 650watt psu does your brother have? again= maker+model+wattage.