Following the successful debut of desktop Skylake K-series CPUs last month, Intel have now finally revealed their comprehensive 6th Generation Core product stack for 2015 and beyond. Built using the brand new 14nm transistor technology, and featuring a substantially revised CPU and GPU architecture that offers considerably benefits over Haswell, there's now a Skylake CPU for every class of mainstream PC.
Although perhaps not quiet as eyecatching as some launches Intel have changed-up their lineup in small but significant ways, beyond the mere adoption of a new architecture. Noteable within the full list of desktop and mobile CPUs is the inclusion of an unlocked (and hence overclockable) K-series design in the 45W segment. Accompanying this new SKU in the 45W range are also two new enterprise-class Xeon CPUs, one of the rare occasions that they've had billing alongside consumer models.
The CPUs launched today are nominally grouped by TDP, and as the definition of 'desktop' has blurred so have notationally mobile CPUs found their way into innovative new desktop designs. Laptops and notebooks have also not been immune to this trend. The so-called 'desktop replacement' laptop has been a fixture for years now, with relatively high TDP as it's eaten away at the traditional desktop market. As a result, even though use cases are broadly discussed, the following CPUs could find their way into a host of new form factors which aren't mentioned.
Skylake-S - Traditional Desktop Mainstay
Skylake-S models are generally what we would view to be classic desktop designs - they feature a replaceable LGA-1151 CPU and are complementary with the wide scalability of Intel's 100-series chipset. If you're assembling your own system, or buy one from a system integrator, in all likelihood you'll be picking up a Skylake-S CPU. There are three clear sub-divisions within the Skylake-S lineup, encompassing the 91W K-series designs we are already familiar with, 45-65W discrete mainstream models, and 35W low-power designs.
Filling out the traditional desktop range are designs starting at the 45W entry-level Core i3-6100, and scaling to the 65W Core i7-6700. Each of the new CPUs feature DDR3L and DDR4 memory controllers, and Intel HD graphics 530, and are dual-core or quad-core parts that present at least logical cores to the operating system.
Catering to demand for low-power desktop systems are a host of new 6th Generation Core SKUs with the 'T' suffix, denoting a TDP of 35W or less. They have a lot in common with their 45-65W counterparts and are generally fully featured Skylake-S CPUs, with minor concessions made in base and turbo clock speeds to achieve these low power targets.
Sitting very much at the budget end of the discrete desktop stack are Intel Pentium processors, distinguishable by their 'G' suffix. Both 35W 'T' models and beefier 47W SKUs are included, and each are at least a dual-core part with Intel HD graphics 530 or 510. Once again the 'T'-class CPUs achieve their comparatively low TDP by restricting CPU and GPU frequencies.
Skylake-U - Low-Power Desktop and Mobile
Just as the Skylake-S caters to the traditional desktop, so Skylake-U helps enable innovative new desktop form factors as well as mainstream mobile designs. Skylake-U finds its way into mini-PC, Intel NUC's and large All-In-One designs, and makes use of a non-removable BGA socket system. Skylake-U is also where you'll find Intel's latest Iris graphics solution, i.e. Intel Iris Graphics 550, now with onboard eDRAM.
The top-end Skylake-U is the 28W Core i7-6567U. A dual-core part with hyperthreading, it tops out at 3.6GHz Max Single Core Turbo from a 3.3GHz reference clock and includes 4MB L3 Cache. Middle of the road Core i5 parts knock down the CPU clock speeds, but retain the standard dual-core with hyperthreading design and 4MB L3 cache. Finally, the Core i3 model dispenses with a Turbo Mode altogether and considerably reduces both maximum GPU frequency (down to 1GHz from 1.1) and L3 Cache (3MB rather than 4).
The 15W bracket is where the Skylake-U undergoes something of a diet, dramatically reducing TDP through lower CPU and GPU frequencies. In addition, 15W Skylake-U parts typically make use of less complex Intel Iris 540 or 520 embedded graphics solution. This design prioritises media so that although raw rendering throughput isn't as high, actual features and support for productivity assignments such as video encoding/decoding are minimally affected.
Two additional entry-level SKUs, the Core i3-6100U and Pentium 4405U, round out the Skylake-U lineup.
Skylake-H - The New High-end Mobile
Sitting at the top of the mobile totem-pole is a CPU class which sees new focus in the 6th Generation Core era. Designated Skylake-H CPUs, these high performance 45W mobile parts include purpose-built designs for home users, enthusiasts and enterprise level customers. It's also for these CPUs especially that memory manufacturers are now releasing high performance DDR4 SODIMMs.
Perhaps the most noteworthy new entrant is the Core i7-6820HK, an unlocked part that can be overclocked on supporting BGA chipsets. Sure to form the backbone of a new range of gaming laptops from the likes of ASUS, MSI, AORUS et al, it's Intel's first foray into bringing overclocking to the laptop gaming crowd.
The Core i7-6820HK is a member of a group of four i7-CPUs all incorporating Intel's quad core design with Hyperthreading technology. All bar one is equipped with 8MB L3 cache and Turbo speeds in excess of 3.5GHz, likely hitting performance levels which could rival a desktop system.
Just two Core i5 models sit in the midrange. Although still quad-core parts they don't support Hyperthreading and feature only 6MB L3 cache, and base frequencies are considerably down on the flagship designs. Nonetheless, they should be tempting options for price/performance oriented mobile gamers.
The entry-level Core i3-6100H is a simple quad-core part by comparison, with half the Level 3 Cache of its i5 brethren and slightly lower GPU speeds. To compensate the base and Turbo core frequences have been increased, ensuring that it should still be no slouch as mobile CPUs go. As with all the Skylake-H CPUs, the Core i3-6100H is equipped with an Intel graphics 530 GPU to aid in video encode/decode and tasks where the power of a discrete GPU isn't necessary.
Rounding out the Skylake-H range are new Intel Xeon SKUs for Enterprise-class users. The E3-1535M and E3-1505M differ little from their high-end consumer counterparts, the chief of which is the inclusion of certain enterprise features as standard such as support for DDR4 ECC SODIMMs.
Skylake-Y - Very Low Power Core M
Rounding out the Skylake family being announced today is the Skylake-Y class of processors for very low power systems. Sitting at a typical TPU of 4.5W, this group of CPUs which fit under the Core M brand umbrella are intended for unconventional designs including embedded systems and new use cases such as the poreviously mentioned Compute Stick. As you would expect from such low power parts base frequencies are considerably reduced, but they're still dual-core hyperthreaded parts with their own dedicated graphics component (in this case, Intel Graphics 515). The major change from more mainstream Skylake processors is the limited memory support, with compatibility with only DDR3L and LPDDR3.
More to come from Skylake in 2016
The CPUs outlined above are merely the first release of Skylake for mobile and desktop systems. They will slowly be phased into the market over the course of Q4 2015 and early 2016, depending on market conditions and demands. In particular, the unlocked Core i7-6820HK will almost certainly be prioritised due to Intel's renewed focus on the enthusiast gaming segment of the market, whilst CPU with more niche offerings will follow.
Despite muddled debut of Skylake in August the CPU range of the whole is looking like it will be remarkably comprehensive by the end of 2015, catering to diverse markets and in particular new use cases where Intel's CPU designs previously saw little penetration. Judging from early reports Skylake-Y CPUs will be of particular interest because they open up so many new opportunities for Intel's hardware, where previously performance was limited or overcosted. The mainstream by comparison continues to be well catered to, with little competition that isn't from Intel's own previous hardware generation.