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1999$, and it is HALF AS FAST as it is a 4 thread instead of an 8 thread machine!
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8 threads doesn't make a computer twice as fast as 4 threads. Hyperthreading lets you run two threads on one core, so they can better utilize the resources of the core in case one (or both) of the threads isn't making maximum use of the core by itself. But it's nowhere close to the performance you would get by just having more cores.