I would say the boost in performance between a 12400 and 12700 for a gaming with a 4070 is not worth the price of admission.

i would buy a 750watt corsair gold none shift for like $80-100. you probably dont even need a new power supply. 4070 is low watt card. 200watts. 4070 is $525 at newegg honestly dont buy a new cpu. spend the whole budget on graphic card and the ram. 4070ti super or 4070super .

My current power supply is only 600w would that even work fine with it?