[spullara]

There is a huge difference between the two. Hyperthreaded cores only give you a speed up in specific situations where additional work can be squeezed into the pipeline.

http://en.wikipedia.org/wiki/Hyper-threading

The speedup is very work dependent and in practice for things like web pages and api servers you generally only get another 20-40% of performance from them rather than a full 100%.

[thrownaway2424]

In other words, you have no idea what the difference is.

A hyperthreaded Intel CPU has M functional units and N decode/issue pipelines.

A non-hyperthreaded Intel CPU has M' functional units and N' decode/issue pipelines.

A hyperthreaded Intel CPU with hyperthreading disabled has M functional units and N/2 decode/issue pipelines.