A Closer Look Part II
A sassy ECS
Below we see the most interesting feature of the X79R-AX: the inclusion of four 6GB/s capable SAS ports. Astute readers will know that these ports were originally part of the X79 chipset specification prior to their last minute removal. According to Intel, they were removed due to out of spec I/O performance being seen under certain temperature and voltage conditions. They are still present on every X79 motherboard but manufacturers have opted to follow Intel and not activate them. ECS have bucked this trend. Since SAS technology is designed with heavy I/O in mind, uses higher signalling voltages and is an enterprise level technology with stringent validation requirements, the chances are that a regular SATA drive will never encounter any problem, although only time will tell.
From left to right we have a pair of SATA 6GB/s ports controlled by a Asmedia ASM1051 chip, four SAS/SATA 6GB/s ports wired to the X79 chipset, four standard X79 SATA 3GB/s ports(white) and finally the X79 SATA 6GB/s ports.
Unfortunately we didn't have a SAS drive on hand to test. To activate the ports, the Intel Rapid Storage Technology driver needs to be installed, hence an operating system cannot be installed from scratch on these ports. We would recommend using the regular X79 SATA ports for the OS and use the SAS ports as regular SATA ports for storage drives that won't encounter high and continuous I/O levels.
The PWM is controlled by an analogue Intersil ISL6366 which is a dual 6+1 phase controller resulting in twelve phases for the CPU and two for the system agent or I/O. While many manufacturers have transitioned to digital PWM systems, the ISL6366 is one of the best performing and most reliable analogue controllers on the market.
Like most boards these days, the drivers and MOSFETs are integrated which saves on board space. They are found on the front and back of the board. They are Fairchild Semiconductor FDMF6705V MOSFETS which have an efficiency rating above 93%, a current handling rating of 43A per unit and up to 1Mhz switching frequency.
The heatsink is solid and heavy. It makes good contact with the components. The pressure of the MOSFET heatsink is slightly weighted to one side due to the screw positions. There shouldn't be any cause for concern as all the chips are in complete contact.
This heatsink has a really nifty feature. It has what ECS calls thermo chromic strips on both sections that change color according to the temperature. On the chipset heatsink, a series of numbers progressively light up as the temperature rises. The tribal image on the PWM heatsink also changes color although it is likely to be hidden by almost all CPU heatsinks. With a fan blowing over the PWM area, only once did we see the color change and the chipset heatsink never hit 50c.
With a windowed case this should be a pretty cool feature, unless of course it is obscured beneath multiple graphics cards.
There are a set of voltage read points onboard for the hardcore overclockers. Unfortunately the ATX power cable gets on the way and hinders accessibility.