How many processors are in an Intel Quad Core?

Question

The Intel site is not clear on this. Red Hat Linux is reporting 8 processors (each with a unique physical ID). I am looking at /proc/cpuinfo. This box is supposed to have 4 cores. I would appreciate a good web link if you could be so kind.

Does anyone know how to locate the CPU ID table in C/C++?

Thanx;

Answer 1

No they are NOT 8 physical cores.



I would explain to you. There is something called thread and it means "the smallest unit of processing that can be scheduled by an operating system".



Intel has a technology called HT (Hyper Threading). By using this technology each physical core will process two thread at the same time, and that causes windows to be deceived and "see" each physical core as two.



All of i7,i5,and i3 processors have HT technology.



So if you have Pentium 4 with HT technology you have single core but the system sees two.

If you have Core i5 then you got actually two cores but the system sees four.

If you have i7 processor then it depends some of them have 4 cores some others have 6, so the system will see 8 for 4 cores and 12 for 6 core.

Answer 2

It's cores, not processors. There are 4 physical cores but 8 logical cores. Intel has a feature called HyperThreading that allows each core to run 2 things at once as long as they're using different parts of the processor. It's not quite as good as having 8 physical cores, but it's pretty close.

Answer 3

The answer is there my friend. QUAD. Quad means 4. its meaning 8 if it has HT technology. which that means is that each core can do 2 jobs at once. so 4 cores and 8 threads

Answer 4

without a model number, this is a guess, but I imagine it's 1 processor, 4 cores, 8 threads



I dunno if it's the same in the Linux world, but each execution pipeline (thread) appears to Windows as a separate physical processor. Each core uses some hyperthreading trickery to make it appear as though it's executing two threads in parallel so the OS reports it as a separate cpu.



Can't help you with the C++ though I'm afraid!

Answer 5

You have only one processor with 4 processor cores.



A quad core processor is a central processing unit, or CPU, that uses four distinct cores, which are rings of magnetic material that read and execute instruction sets within a CPU. Other CPU components, in comparison, carry instructions to and carry results out of CPUs. The main benefits of a quad core processor over a processor that has fewer cores -- such as a dual or single core processor -- stem from the fact that the quad core processor can divide processing work between more components.



Multitasking

Multitasking, or running multiple computer software programs simultaneously, is not beyond the capabilities of dual core processors. However, when users run multiple, "intense" programs with dual core processors -- such as video games, video encoding programs and other programs that use up lots of resources -- computer performance can suffer. This is because dual core processors can only divide computer operations between two cores, or mini operating stations. In comparison, quad core processors can divide operations between four cores. This allows a quad core processor to dedicate more processing power from individual cores to individual programs. For example, a quad core processor could dedicate one core to a video-editing program, a second core to a Web browser, a third core to a word processor and a fourth core to a virus-scanning program.

Video Encoding

A quad core processor is better equipped for video encoding than a dual or single core processor. Video encoding refers to the storing, transmitting and interpreting of video files; it's an especially important function for computer users who regularly upload DVDs and Blu-ray discs onto their hard drives, as well as for users who regularly burn movies and videos onto recordable discs. Quad core processors are more efficient at the task of video encoding, as video encoding relies heavily on single instruction multiple data, or SIMD, instruction sets. Processing SIMD instruction sets requires the use of multiple processing components, which are necessary for applying the same operations to multiple units of data. Due to their additional cores, quad core processors can more easily apply these operations than their dual and single core counterparts.

3D Rendering

3D, or three-dimensional, rendering refers to the process of a computer graphically interpreting and representing 3D data in two dimensions. In comparison to single and dual core processors, quad core processors provide superior 3D rendering, which allows for on-screen computer graphics that are more realistic. As is the case with video encoding, quad core is a superior processing technology for 3D rendering because 3D rendering relies heavily on SIMD instruction sets.

Gaming Benefits

Apart from being able to provide superior 3D graphics, a quad core processor can enhance other aspects of computer video gaming -- provided that the game a user is playing has been developed specifically four a quad core processor-based system. Because quad core processors have those four mini processing stations or cores within them, game developers can dedicate certain types of game data to specific cores. For example, one core could process graphics, another could process audio, another could process game physics and another could process artificial gaming intelligence.