PCB Design and Functionality
I doubt that we will be wrong if we say that designing Intel X79 Express based mainboards has become significantly more difficult than designing mainboards on the previous chipsets, because the lack of free space has become a much bigger problem. At least four, and in case of Asus P9X79 Deluxe mainboard all eight memory DIMM slots are now located on both sides of a large processor socket.
Processors consume a lot of power, which means that they need stable voltage regulator circuitry with proper cooling. This mainboard uses DIGI+Power Control voltage regulator working as 16+4+2+2, where two additional pairs of phases are responsible for the memory. Free PCB space is in such dramatic shortage that some of the voltage regulator components had to be moved to the back side of the PCB. They are covered with an aluminum plate that also helps to dissipate heat, but the major thermal load still falls on the four primary heatsinks. Heatpipes are used to tie pairs of heatsinks into a single cooling contour and all of them are fastened with very reliable screw-on retention. It is crucially important to ensure proper CPU cooling, too, that is why it is great to see two fan connectors for the CPU fans onboard.
For the expansion card you can use two PCI Express 2.0 x1 slots and four slots that will support the upcoming third generation PCI Express cards. There are three slots for AMD Quad-GPU CrossFireX or Nvidia 3-way SLI graphics configurations. Two graphics cards will work at full speed, and once you install the third one the speed layout will change to x16/x8/x8. The fourth slot works as PCI Express 3.0/2.0 x8.
Asus engineers faced certain challenges not only when they tried to lay out the upper part of the PCB with a large processor socket, several memory DIMM slots and processor voltage regulator circuitry. The lower part of the PCB is also suffering from severe shortage of free space, because the functionality of the new Intel X79 Express chipset hasn’t really increased compared with the latest Intel chipset, and they need to use a variety of additional controllers to ensure that their product meets contemporary standards and expectations. USB 3.0 support is delivered by three ASMedia ASM1042 chips. Two of them provide six USB 3.0 ports on the back panel using the VIA splitter, and the third one is used for an onboard pin-connector offering two more USB 3.0 ports. Besides two SATA 6 Gbps and four SATA 3 Gbps ports provided by the chipset, they have Marvell 88SE9128 controller for two more SATA 6 Gbps ports. And ASMedia ASM1061 controller brings two eSATA 6 Gbps ports to the mainboard back panel.
The back panel of Asus P9X79 Deluxe has the following ports and connectors:
- Four USB 2.0 ports, eight more are laid out as four onboard pin-connectors;
- “USB BIOS Flashback” button;
- Wi-Fi/Bluetooth 3.0 module;
- Six USB 3.0 ports (blue connectors) implemented via two ASMedia ASM1042 controllers and VIA splitter, the third controller like that provides an additional internal pin-connector for two more USB 3.0 ports;
- Optical S/PDIF and six analogue audio-jacks provided by eight-channel Realtek ALC898 codec;
- Two Power eSATA 6 Gbps ports implemented via ASMedia ASM1061 controller;
- Two local network ports (network adapters are built around Gigabit Realtek RTL8111E and Intel 82579V network controllers).
I would like to specifically point out that there is a special “USB BIOS Flashback” button and a special white USB 2.0 port, which will allow you to easily update your mainboard BIOS. All you need to do is connect a drive with the new BIOS version, press the button and wait. You don’t need any utilities, you don’t need to access the BIOS or load the operating system, you don’t even have to complete the assembly of your PC. This technology should work even if you don’t have the CPU or the memory installed: all it needs is power for the mainboard.
Like other Asus mainboards, the new Asus P9X79 Deluxe uses convenient wide “Q-Slot” latches on the graphics card slots and one-sided Q-DIMM latches on the memory slots. Besides the glowing Power On and Reset buttons and the “USB BIOS Flashback” button on the back panel, there is a “MemOK!” button that allows the mainboards to successfully boot even if it experiences memory problems, and “Clear CMOS” button for restoring all the settings to their defaults. “Q-Led” diodes will help you quickly determine at what stage the booting stalled, and the POST-code indicator will help to perform more detailed diagnostics. TPU switch (TurboV Processing Unit) will allow overclocking the processor automatically, and the EPU switch (Energy Processing Unit) will help enable a more optimal mode in terms of energy-efficiency. Besides two connectors for the CPU fans, there are four more four-pin case fan connectors. All four allow adjusting the fan rotation speeds, even for the three-pin fans, although the rotation speed control for the processor fans will only work with the four-pin fans.
For your convenience all Asus P9X79 Deluxe specifications have been summed up in the following table: