Hyper-Threading: Differentiating Core i7
So now we have Core i7-800s on LGA 1156 and Core i7-900s on LGA 1366. Confusing, yes. But I’ve tried to make it clear here, at least, that what makes an i7 an i7 is its inclusion of Hyper-Threading technology. Indeed, Intel also uses clock rate as a differentiator, and at least in theory you should get more Turbo Boost from an i7-800-series CPU than an i5 as well.
As you probably already know, Hyper-Threading is Intel’s simultaneous multi-threading technology that presents each physical core as two logical cores to an operating system. Thus, when you open the Task Manager on a Hyper-Threading-enabled Nehalem-based CPU, you see eight threads. This doesn’t mean you suddenly have the equivalent of an eight-core processor. Instead, Intel duplicates certain resources in each physical core to make the technology available; it’s better to think of Hyper-Threading as allowing the execution resources on a quad-core i7 to be better-utilized in threaded workloads.
We know that MainConcept Reference, for example, is well-threaded. By simply turning Hyper-Threading on, our transcoding workload falls from 1:48 to 1:26.
Similarly, the latest version of AVG’s anti-virus software realizes a massive gain thanks to Hyper-Threading. Less-optimized or simply multi-tasked environments will yield less-pronounced results, but there certainly seems to be a reason to at least consider a Core i7 if you’re able to benefit from what Hyper-Threading offers.
