Handling Threads in quad core processor

This depends on the exact processor line and model.

Intel's Core i7, i5, and i3 series can handle 2 threads per core, so any quad-core model could handle 8 threads.

AMD's Athon, Phenom, Sempron, and Opteron chips, on the other hand, are designed around a 1-thread-per-core model.

At the other extreme end, are the SPARC Niagara series of server chips, which can handled anywhere from 8 to 16 threads per core.


All this isn't free. Thread count per core comes at a cost - the more threads per core, the lower performance each individual thread has. That is, using the same hardware, if I run one thread on a core, that thread will run faster than 2 similar threads, even if the threads are independent.