High-End Processors from Intel
So, it is Intel that will play the first fiddle in the top-end market segment. And, surprisingly enough, the company offers not only different CPU models but also different platforms here. The LGA1336 platform is positioned as the main top-end solution. On the other hand, you can buy a $200 and more expensive CPU even for LGA775 or LGA1156. The internal competition and the availability of all the three platforms in the top price segment is an indication of certain flaws in the company’s marketing policy, but here two out of the three platforms can coexist thanks to their unique features.
The benefits of LGA1366 solutions are obvious. It is exclusively for this platform that Intel offers six-core CPUs whereas quad-core LGA1366 processors differ from their LGA1156 counterparts in having a triple-channel DDR3 SDRAM controller. On the other hand, this platform is not without downsides for all its elite status. Coming to desktop PCs from the world of servers and workstations, it doesn’t have a suitable system architecture: the controller of the graphics PCI Express bus resides in the chipset which calls for a high-speed QPI bus to connect the CPU to the chipset. The addition of two QPI controllers into the main chips makes LGA1366 systems consume more power in comparison with LGA1156 computers.
Core i7-900. This series combines rather variegated processors which are designed for the LGA1366 platform. In fact, there are two varieties of products with the Nehalem microarchitecture within this series. The first variety is quad-core CPUs based on 45nm dies, and the second variety is six-core CPUs with 32nm dies. The quad-core models have clock rates of 3.06 to 3.2 GHz, 8 megabytes of L3 cache, and support triple-channel DDR3 SDRAM. They feature all the performance-boosting technologies available today: Hyper-Threading for virtual CPU cores and Turbo Boost for automatic overclocking. The six-core CPUs have higher frequencies (3.2-3.33 GHz) and 12 megabytes of cache. Otherwise, they are similar to their quad-core LGA1366 counterparts in their specs. Particularly, they also have a triple-channel memory controller and support Hyper-Threading and Turbo Boost.
It must be noted that there is a very slim separating line between the quad- and six-core CPUs for LGA1366 systems in terms of model names. The model names up to i7-960 are quad-core CPUs whereas the i7-970 and higher models are six-core ones. The senior Core i7-980X is additionally referred to as Extreme Edition which means that you can overclock it by changing its frequency multiplier.
Interestingly, the LGA1366 platform is likely to have the longest lifecycle among all the platforms available today. It is going to be replaced no sooner than in the end of the next year. Therefore this platform can be recommended for users who like to upgrade their computers regularly.
The LGA1156 platform looks like a more mature solution than LGA1366 because it came out later and its designed was optimized by integrating the PCI Express controller into the CPU. However, the senior CPU models for this platform have lower frequencies and are equipped with a dual-channel memory controller. Most importantly, they only offer one PCI Express x16 but which, even though splittable in two, limits the performance of multi-GPU graphics subsystems. As a result, many LGA1156 processors, even though top-end solutions, are positioned lower in the product hierarchy than their LGA1366 counterparts.
Core i5-600. These are dual-core LGA1156 processors based on a 32nm semiconductor die that additionally incorporates a graphics core die. Such processors are identified by the OS as quad-core ones because they support Hyper-Threading which enables each physical core to execute two instructions threads simultaneously. Top-end models from the Core i5-600 series have clock rates of 3.46 to 3.6 GHz and 4 megabytes of L3 cache. They also support Turbo Boost and to automatically increase the clock rate when one core is idle. The integrated memory controller is compatible with dual-channel DDR3 SDRAM at 1067 or 1333 MHz.
Core i5-700. The junior series of quad-core LGA1156 processors also has its representation in the above-$200 category. This is the Core i5-760 model which is based on a 45nm die and has a clock rate of 2.8 GHz. It supports Turbo Boost but doesn’t have Hyper-Threading. Therefore, like the Core i5-600, it is identified as a quad-core CPU by the operating system. The Core i5-670 has 8 MB of L3 cache and its integrated memory controller supports dual-channel DDR3-1067 and DDR3-1333. As opposed to the 600 series, the 700 series have no integrated graphics core.
Core i7-800. These quad-core LGA1156 processors are the masters of the top-end market segment. Although based on the same semiconductor die as the Core i5-700, they have higher clock rates (2.8 to 3.06 GHz) and support both Turbo Boost and Hyper-Threading. As a result, a Core i7-800 is identified by the OS as an eight-core processor. Besides, the Core i7-800 features a faster memory controller which supports not only DDR3-1067 and DDR-1333 but also DDR3-1600. The Core i7-800 has the same amount of cache as the Core I5-700, which is 8 megabytes.
Right now, the LGA1156 platform looks highly appealing but it is getting closer to its demise. In a couple of months it will be replaced with the new LGA1155 platform which will support more advanced CPUs working at higher clock rates. The two platforms will be incompatible and there will be no LGA1156 processors faster than what is already available.
As for the LGA775 platform, there is no reason for it to be in the top-end market sector in late 2010. We can only view it as a reminder of the highly successful Core 2 Duo and Core 2 Quad series which helped Intel beat its opponent in terms of CPU performance back in 2006. In other words, the Core microarchitecture of the LGA775 processors is just as outdated as the Stars one, but Intel, unlike AMD, does not even try to increase the clock rates of its old CPUs and offers 2- or 3-year-old products at high prices.
Core 2 Duo. The dual-core LGA775 CPU series based on a 45nm core is available in the top price segment, too. There is but one model, Core 2 Duo E8600. This CPU has a clock rate of 3.33 GHz and a 333MHz system bus. It also has a shared 6MB L2 cache.
Core 2 Quad. There are several quad-core LGA775 processors in this market segment. These are models with clock rates of 2.83 to 3.0 GHz and a 333MHz system bus. By the way, a quad-core LGA775 processor is in fact two dual-core semiconductor dies within a single package. Therefore the L2 cache, which is 12 MB large, is divided by half between the two pairs of CPU cores.
The next table shows the specifications of all top-end CPUs from Intel available today.