There are two types of answers to your question: (1) "How many threads can a quad-core processor handle simultaneously?" - this depends on the exact model of processor. At the bare minimum, it can...
There are four execution units (EUs) in a core 2 quad processor.
Core 2 is the technology. Without the word quad, there are two EUs. With the word quad, there are four EUs.
There is still one low...
Four independent cores into a single package composed of a single IC. A dual-core processor contains two cores, and a quad-core processor contains four cores.