Question : Windows Task Manager and CPU Usage Windows

I have a Gateway desktop G710 with a Pentium 4 3.4 GHz and 4gb memory.  The two CPU windows displayed in the Windows Task Manager generally, more often than not, show basically an identical track of CPU usage.

Sometimes however, they can vary significantly.  I don't understand as I don't believe the Pentium 4 is a dual processor.  I am I wrong?  Why do they display differently sometimes?

Answer : Windows Task Manager and CPU Usage Windows

HyperThreading, which I believe all (or most) P4's that were single core and 3.0 GHz or greater support HyperThreading.  HyperThreading will show the CPU as if it is TWO processors.  This is because HyperThreading (HT - in Intel terms; different from HT in AMD terms (which is HyperTransport)) can execute both integer and floating point operations at the same time.  The Integer aspect and the Floating point aspect appear as individual processors.  This is why sometimes, one may be busier than the other.  Some tasks may be more floating point intensive while others may be more Integer intensive.