Skylake: A Deep Dive into Intel’s Latest Architecture

An IT pro’s guide to Intel’s most significant processor in a decade. By Matt Whitlock

Skylake, the successor to Intel Corp.’s Haswell and Broadwell processors, is the latest micro-architecture design from the chipmaker. And that’s significant because a new micro-architecture represents fundamental changes to the very underpinnings of a processor.

According to Intel, Skylake is its most significant processor [micro-architecture] in a decade, due to major advances in power efficiency and wireless capabilities. Skylake’s design stems from Intel’s engineering research center in Haifa, Israel, which produces some of the company’s most innovative and advanced processor designs. Skylake truly showcases this team’s micro-architecture design prowess in that it has been engineered to be the foundation of a broad array of processor types. Skylake “Y” series designs, for example, can be scaled as low as 4.5W for phones and tablets, and scaled up to 91W for ultra-fast “S” series desktops and (inevitably) servers. Skylake’s predecessor, Broadwell, was flexible, but Skylake is truly versatile.

As expected, Skylake boasts numerous improvements/tweaks in branch prediction to enhance the flow in the instruction pipeline as well as in prefetching, buffering, page mishandling, and other areas that will increase performance as this generation of processors evolves. The modular, more “mobile first” approach to Skylake means, however, that there is little performance gain, clock for clock, to existing desktop parts. Few desktop users upgrade generation to generation, but upgraders two or three generations back will enjoy a healthy performance boost.

Tech Improvements
Skylake’s performance improvements will be far more apparent in power-restricted scenarios. Advanced power management, comprising both power delivery and frequency control, has been a primary focus for designers. The idea behind Speed Shift (a marketing term the company uses to describe some of these new power features) is to give the processor more ability to react dynamically to workloads by using untapped parts of the processor, gating off unused sections, clocking down, or duty-cycling when performance isn’t imperative. Some of these features require OS support, and Intel has been quick to note that there was some collaboration with Microsoft during Skylake’s development.

Another notable area of improvement is security. Skylake adds support for Intel Software Guard Extensions (SGX) and Memory Protection Extensions (MPX). The former essentially serves to “sandbox” processes in their own environment, reducing risks of a rogue process or malware interacting with other processes inside and outside of that sandbox (or “enclave,” as Intel calls it). The latter, MPX, aids in buffer-overflow conditions that are so frequently the source of system infiltration.

Skylake adds a number of other technological enhancements as well, such as bringing DDR4 support to the mainstream. Haswell-E, Intel’s enterprise-grade LGA2011-3 socket, required those super-expensive RAM modules, but thankfully Skylake serves as a bridge by keeping legacy support for DDR3L.

Another area of focus, as it has been for Intel across several generations, is graphics. Like the move from Sandy/Ivy Bridge to Haswell, the performance and power efficiency of onboard graphics is dramatically improved. A number of new features and capabilities have made their way into Skylake, such as DirectX 12 support, 16x MSAA, adaptive scalable texture compression, multiplane overlays, and so on.

With this generation of graphics, Intel has largely cleared out the market for low-end, discrete graphics hardware at the sub-$75 to $99 price point, but that’s been the case for quite a while now anyway. The largest impact will be (again) in mobile parts, especially phones, tablets, and low-power Ultrabooks that generally rely on integrated graphics.

Wrapping It Up
Skylake is an engineering marvel. In more traditional form factors, it will enable thinner, lighter, and more powerful Ultrabooks and laptops. However, its biggest improvements are designed to help it compete in markets currently dominated by ARM-powered systems, like phones and tablets. Intel has been trying to crack these markets for years, and Skylake is its best weapon yet. As Windows on tablets is embraced more broadly, Intel should see some success there. Phones are a tougher nut to crack.

Who knows? What just might do the trick is maybe an Intel-powered Surface phone that when docked can run all your x86 programs.