The new Intel Skylake: era of great expectations
Large, perhaps too large hopes are placed on the new generation of desktop processors from Intel. Promises of the company in respect of generation, codenamed Skylake was generous. Here we briefly summarized them in our material, discussing Broadwell chips: «It (the architecture Skylake) are expected to bring significant performance gains and will mark the beginning of a new wireless era in the PC world – how, in terms of displays, and in relation to charging technologies and data transfer». It was then. Let’s see what we have today.
Unfortunately, this part of the text is abound with information as you might expect. Probably the first time in its history, Intel releases a radically new microprocessor architecture, which is unknown almost no specific details. The company, for example, says nothing about the number of transistors in a new chip, is silent about the physical size of a silicon wafer, even not clear what changes have been made compared to the predecessor Skylake. No ordinary colorful pictures of the «naked» CPU – i.e. only the core without the protective metal coating.
As you know, Skylake is not the first generation microprocessor that uses a 14-nanometer manufacturing process is a «privilege» falls on the family of Broadwell, which made its debut on the market at the end of last year. Almost immediately after the appearance of the first wave of Broadwell chips Intel announced that models designed for specific market segments, will be postponed at least for one year or more. In light of this information, it was logical to assume that the company will delay the announcement Skylake until the market is sufficiently saturated with Broadwell chips, and only then will release a new microarchitecture. Instead, Intel released Skylake in a few weeks after the appearance of the first desktop processors based on Broadwell.
Perhaps the reason for this step is associated with news about the delay Kaby Lake, the successor to Skylake and Broadwell, which should be produced on a new, 10-nanometer manufacturing process. The company clearly has more serious difficulties in the attempt to follow the famous Moore’s Law, while used the last fifty years of microprocessor technology is coming to the inevitable limit of their capabilities.
Anyway, the Skylake architecture market is already a fact. In addition to 14-nm technology production, it comes with the new microprocessor with the socket (LGA1151), integrated graphics core of the new generation (Intel HD 530), new chipset (Z170) and support the new DDR4 memory.
If you carefully follow the development of the Intel, you will immediately notice that the Z170 in fact almost identical to its predecessor, the Z97. The difference between them is mainly evolutionary in nature. For example, the number of available USB 3.0 ports increased from 6 to 10. The new chipset supports a total of 14 USB ports. C Z170 and also debuted a new 3.0 version of the internal DMI (Direct Media Interface) interface between North and South bridge chipset. This increases the theoretical bandwidth from 2.5 GB/s to 8 GB/s (i.e. 3.2 times).
Other theoretical improvements
One of the key innovations that brings Skylake, is support for DDR4 memory, which in theory should provide a significant improvement in the overall performance of the subsystem CPU-RAM. We say «in theory», as compared to DDR3, the new memory offers high bandwidth, but higher latency (or higher latency when addressing for all memory blocks). For example, the highest now available in the market classes of memory DDR4 (DDR4-3400) according to specifications is the latency 16-18-18-36. For comparison, the fastest DDR3 memory (DDR3-2133) boasts increased latency order 8-10-10-27. In other words, the clock frequency DDR4 1.6 times higher than comparable DDR3, but the latency of the last 1.6 times less. Given the fact that the performance of the most massively used application today is more dependent on the latency path than the transfer rate of (memory bandwidth), the transition to DDR4 is unlikely to have an instant, positive impact in this regard.
This does not mean that DDR4 is bad – quite the contrary. Just to reveal the full potential of the new memory will need more time and optimization of popular programs.
A few words about the first bird from the nest Skylake. Hard task to pave the way for a new architecture was entrusted to two chips: the Core i7-6700K and Core i5-6600K. The letter «K» in their names suggests that it is a CPU with an unlocked multiplier, i.e. they promise simple and flexible for overclocking (increase their nominal clock frequency). It gave Intel the base to position the first two Skylake processor as a product-oriented video game lovers and enthusiasts.
Here is a more detailed picture of the two chips. More powerful (and expensive) of these is the Core i7-6700K with four cores and Intel Hyper Threading (i.e., in total 8 threads). The chip has 8 MB cache in the third level (L3) and operates at a frequency of 4.0 GHz. Built-in CPU memory controller supports DDR4 at 2133 MHz and DDR3 at 1600 MHz.
A more affordable Core i5-6600K also has four cores, but comes without the support of Hyper Threading. Its nominal clock frequency is 3.5 GHz. The smaller L3 cache (6 MB), and again supported memory DDR4 and DDR3L.
The recommended starting prices of both processors: $ 350 for the Core i7-6700K and 243 dollars for Core i5-6600K.
The first practical texts of the two chips Skylake are somewhat contradictory. Despite a generous initial promises now Intel behaves quite conservative in their forecasts of the productivity gains that users can expect from the i7-6700K and i5-6600K. According to them, Skylake is 10% faster than last year’s Devil’s Canyon (Haswell generation), up to 20% faster Core i7-4770K from conventional generation Haswell and is approximately 30% faster than the chip Core i7-3770K Ivy Bridge.
The results show processors to confirm this. In some applications – when transcoding video, rendering and other similar heavy series of successive operations Skylake able to demonstrate 30 — and even 40-interest superiority over previous generations of processors.
However, in more common applications (including games) the growth is much more modest – in the range of 5-10 percent.
With this in mind Skylake is hardly a particularly good upgrade for users of computers with Haswell chips, or even Sandy/Ivy Bridge. Especially given the fact that the transition to Skylake will mean the purchase of a new motherboard, RAM modules (DDR4), and probably cooling as the LGA1151 socket has a slightly different mounting mechanism.