As you remember, Lynnfield processors found their way into two processor families: Core i7 and Core i5. Clarkdale CPUs, however, will exist in three incarnations: Core i5, Core i3 and Pentium. And it means not only that Clarkdale retail price will vary in very broad intervals, but also that Intel will offer different Clarkdale modifications with more than just different clock frequencies. To differentiate between multiple Clarkdale families they will also take into account disabling of Hyper-Threading and Turbo Boost technologies and manipulating the cache-memory size. As a result, there will be five different Intel processors for LGA1156 platform including Lynnfield models. We summed up their basic specifications in the table below:
Note that top Clarkdale processors from Core i5 family are targeted at about the same market niche as junior Lynnfield CPUs. Intel obviously has very high expectations of their new dual-core processors, believing that their high clock frequencies and Hyper-Threading technology support will help them compete successfully against quad-core processors.
There will be a total of seven different Clarkdale models available in the market:
Core i5-600 processors represent the most feature-rich Clarkdale version. They support Turbo Boost and Hyper-Threading technology and their nominal clock frequencies surpass the frequencies of quad-core Core i7 CPUs even with a working Turbo Boost technology. Moreover, there are two top models in the Core i5 family: Core i5-670 with maximum clock frequency of 3.46 GHz and Core i5-661 working at 3.33 GHz and graphics core overclocked to 900 MHz – the highest frequency among all other available models.
Core i3-500 processors do not support Turbo Boost technology that is why they can fall seriously behind Core i5 during single-threaded load although they work at very similar nominal frequencies. However, Hyper-Threading support is still in place that is why these processors can also be considered a suitable alternative to inexpensive quad-core solutions, just like Core i5-600.
The Pentium processor has the most modest feature list of all. This CPU doesn’t support Turbo Boost and Hyper-Threading that is why the operating system sees it only as a dual-core processor. Moreover, this inexpensive processor has a graphics core working at a lower frequency and doesn’t support DDR3-1333 SDRAM. In other words, it is a typical budget solution with all sorts of “delicacies” blocked right from the start. Besides, L3 cache in Pentium processors has been reduced to 3 MB.
I have to say that Intel decided not to make Turbo Boost technology in Clarkdale processors as aggressive as in Lynnfield CPUs. All new Core i5-600 processors supporting this technology can increase their clock frequency by one increment in case both cores are loaded and by two increments in case of single-threaded load. It means that maximum frequency increase for Clarkdale processors is only 266 MHz. Lynnfield CPUs, however, can increase their frequency by 4-5 increments, i.e. the total increase my reach 667 MHz. This introduces certain adjustments into the correlation between the clock frequencies of dual- and quad-core processors: under partial load the performance difference between Lynnfield and Clarkdale processors may get lower. The table below shows the frequencies of Core i7 and Core i5 LGA1156 processors supporting Turbo Boost under different type of operational load:
While in LGA775 systems dual-core processors were often faster than quad-core ones due to their higher clock frequency, in LGA1156 systems we will see the same situation less frequently. Due to Turbo Boost support, quad-core Lynnfield CPUs will be overclocked automatically when the load becomes less intense and only one or two cores are actually busy. This way their clock frequency will get close to that of dual-core processors. Therefore, similar price of Core i5-670 and Core i7-860 shouldn’t mislead you: it is justified not that much by the computational performance of the top Clarkdale CPUs, but mostly by broader functionality due to integrated graphics core.