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Does the i7-920 have four or eight cores?

By H3llion
May 8, 2012
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  1. Is the i7 920 8 core CPU? I know that it says that it has 4 cores and HT which means each core counts as 2 therefore 4 > 8 cores. But is it really an 8 core CPU or would you still call it a quad core?
     
  2. Blkfx1

    Blkfx1 TS Addict Posts: 890   +171

    Wouldn't It still be considered a QUAD core? the threads do not count as actual cores. Maybe someone with more knowledge on the matter will chime in. I am interested to know myself.
     
  3. LNCPapa

    LNCPapa TS Special Forces Posts: 4,336   +280

    It's a quad core CPU - just like the 970 and higher procs are NOT called 12 core CPUs even though they appear to be capable of executing 12 simultaneous threads. In fact, you can only expect 20-30% the performance of an actual core from hyperthreading on applications that can actually use them.
     
  4. slh28

    slh28 TechSpot Paladin Posts: 1,925   +170

    I'm not an expert but here's my understanding: It's a quad core CPU because there's 4 physical cores but HT makes the OS send 2 sets of instructions to each core, so applications recognise 8 threads in total. It's not the same thing as a true 8 core CPU because when two threads are running on a single core, the number of execution units, cache, etc. are split between those threads.

    Here's an analogy: a true 8 core CPU is like having 8 workers and a 4 core CPU with HT is like having 4 workers but giving them two things to do at the same time. You're not going to get double the productivity from the 4 workers but if they're good at multitasking then you might get a 10-20% increase in total productivity.
     
  5. Razer

    Razer TS Enthusiast Posts: 131   +11

    physically it's a quad core, but since it has 8 threads so technically it can perform just like 8 core CPU..
    based from threads (from other forum) and articles I read.. it's still considered as quad core CPU..
    but, I'm not expert on this
     
  6. captaincranky

    captaincranky TechSpot Addict Posts: 10,824   +922

    As I imagine it, (and "imagine" is exactly the word most appropriate), there are 4 discreet cores in the i7-920. However there is redundancy in many of the logic circuits. When there is excess data to be processed, the main core is tasked to shunt some of it to the duplicate circuits.

    Perhaps picture something like some of the cars stuck in traffic on the same highway, being allowed to pass on the shoulder of the road. (Best analog I could come up with :confused: ).
     


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