Both use one "core" or module.(c/m)
Each c/m has several processing circuits. Some are duplicated and some less used functions have only one.
In the case of FX, most are duplicated, making each module function close to a full core.
In the case of intel, hyperthreading works a bit differently.
A second thread can use the resources not in use by the first thread.
In the case of FX, I guess that you get 90% of the performance on the second thread.
But, the basic architecture of FX was poor so single thread performance was not good. About 1400 passmark rating.
In the case of Intel, I guess that the second thread is about 35% effective, but the basic single thread performance due to architecture was much higher. perhaps 2000-2500 passmark