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Old December 29, 2011, 06:47 AM
frontier204 frontier204 is offline
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Location: Ottawa, ON
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My System Specs


What does your OS and BIOS call the CPU? I'd trust that first (and wait for the next CPU-Z) to see what happens. EDIT: well it looks like CPU-Z messed up, but check BIOS anyway

AMD has never used HyperThreading. People equate the way Bulldozer shares a floating point unit to HyperThreading.
They decided to create a “dual-core” module that shares some resources (the front-end engine, the floating-point unit, and the L2 memory cache, see Figure 1)
Inside the AMD Bulldozer Architecture | Hardware Secrets

Intel® Hyper-Threading Technology (Intel® HT Technology)1 uses processor resources more efficiently, enabling multiple threads to run on each core.
Intel® Hyper-Threading Technology

From what I gather, since I can't find a detailed breakdown of a Sandy Bridge core, HT shares ALL the resources of a core (floating point, arithmetic logic unit (ALU) stuff, L1 cache, etc) among two threads. If you run two threads on Bulldozer however, you still get two L1 caches, 2 sets of ALU, but one L2 cache (that's meh because lots of CPUs break L2 cache to be shared between cores), and only one FPU (BIG performance penalty if your task is floating point heavy like F@H, physics, some ray tracing, etc.). If you're running an integer or branch-heavy load (e.g. most database / server stuff) you should get "true" 8-core performance.
"The computer programmer says they should drive the car around the block and see if the tire fixes itself." [src]
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