Careful, most MB vendors ship their MB 'stock" with PBO turned on.
PBO Is overclocking and thus not really supported.
Your dashboard, are there many dials in the Red or Yellow?
Turn off Core Performance boost and then PBO boost.
At this setting all your cores will/should run up to Base but no further.
These settings will drastically lower the CPU temp.
Run with this for a while, when all is well proceed to the next step where you will set a static clock
on a per CCD basis. Then there are MANY other things you can do, but at this time you want to get in the ballpark
Luck.