All core oc is not worth becuase:Not entirely true. You can either do a lot of goofy stuff to try and amp up your boost clocks (use PBO, fiddle with LLC settings), or you can go for static OC which will get you some decent gains in games that spawn a fair number of threads. I think 4.2 GHz static is attainable on almost any 3700x in games. I know that my 3900x, despite being able to boost to 4.6 GHz, runs games faster with a static OC of 4.4 GHz (or even 4.375 GHz) since the boost duration is so short. Max boost for a 3700x is supposed to be 4.3 GHz and PBO + Auto OC is often quite useless. If I had a 3700x, 4.2 GHz static on all cores would be my target for games. Or at least 4.15 GHz.
1-cpu wont downclock in iddle and is always on max voltage.
2-i can oc to 4250mhz, but performance is same as with all settings default so its not worth it because cpu will degrade very fast without downclocking/iddle voltage.