How to solve it? Get it back to normal.
In Windows for FX 83xx Series processors it will always show 4 "Physical" cores and 8 "Logical Cores". This is normal.
I have a FX8350 and this is what Windows Task Manager shows:
This is because each CPU Physical core has 2 logical cores.
In CPU-Z is shows my processor with 8 cores and 8 threads:
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