After the launch in 2014 of a Z97 chipset that will not change much compared to the Z87, beyond compatibility with an ephemeral Broadwell, the launch of the Skylake platform in 2015 has been accompanied by major changes next chipset with the Z170. And this is - this time - not as a matter of nomenclature.
The most fundamental change concerns the interconnection between the processor and the chipset. To recap, Intel uses a x4 PCI Express link to connect the two components, but renames behind the marketing name DMI. Since 2011, the DMI bus is version 2.0, indicating that it is actually four lines PCI Express 2.0 bandwidth limiting to 2 GB / s in each direction. With the Intel Z170 finally passes the DMI PCI Express 3.0 lines, doubling de facto bandwidth to 4 GB / s in each direction.
The Z170 also extends the concept of flexibility introduced with the Z87. Remember, the idea is to allow the use of I / O lines to the internal chipset to link the choice of SATA ports, USB 3.0 or PCI Express lanes to connect third-party chips. These internal ports were equivalent to PCI Express 2.0 lanes on the Z87, here we go with 3.0 lines, and their number from 18 to 26 in total.
In practice it has obvious limitations. For example the first six ports will only be used to manage USB 3.0 ports. 20 PCI Express lanes are relatively flexible and are groupable if desired in groups of 4 where they can be used to configure SATA Express ports for example. In absolute terms it still remains limited to a maximum of six SATA ports managed by the chipset natively, and now native 10 USB 3.0 ports (six against previously). All additional lines however possible to interconnect more additional chips which will allow manufacturers to stand out from each other. The fact that these ports are in the 3.0 format also doubles the bandwidth, 1GB each way now for chips interconnected x1 (the classical case).
Back to the tensions of regulations by the motherboard
This may be one of the most surprising changes Skylake platform: after joining the regulation of tensions directly in Haswell, Intel decided to remove it again in Skylake. In practice, where the motherboard not provided two tension socket to simplify designs, we are four now.
Thus, the motherboard provides a specific diet plan for the CPU cores and the L3 cache (Vcore, which will be derived to power the chip ring bus), a plan for the graphics cores Vgt, a plan for the memory controller (VDDR) and VSA for "chipset" part (System Agent, which includes the management of PCI Express and DMI bus between other).
with the advent of the integrated regulation, the impact of the motherboard on overclocking was largely leveled. We'll see if, logically, things have changed and overclocking becomes a point of difference for motherboard manufacturers. However, remember that this change will evolve in the future as in the last IDF, Intel confirmed that the reason for the return to external regulators was linked only to models with TDP is 4.5W. At this power level, integrated regulators were against-productive and increased consumption, Intel engineers even indicating it would be preferable in the future to use external control for these models and an internal control for other .
the most visible change for users is of course the arrival of a new type of memory DDR4. This is not exactly a first since the high-end platform Haswell-E had already passed the DDR4 in August 2014 .
Skylake thus marks the arrival to the consumer version and this is the type of memory that is privileged the motherboard manufacturers, Intel is likely pushing behind them that do offer DDR3 as on some models, usually entry.
Five models midrange
For this first comparative Z170 motherboards, we focused on what we call the middle range, a criterion which is defined by both the price (around 150-170 euros) and especially by a technical feature: the management of at-least two PCI Express ports by the processor, to allow for example for those who wish to support multi GPU SLI and Crossfire, or more generally two 8x PCI Express cards (a graphics card and a . PCI Express SSD for example)
Six cards therefore meet these criteria:
ASRock Extreme4 Z170
MSI Z170A Krait Gaming
MSI Z170A SLI Plus