[nextpage title=”Introduction”]
The ASRock X99 Extreme6/3.1 is a top mid-range motherboard for the new Intel high-end “Haswell-E” processors, based on the LGA2011-v3 socket. It includes three PCI Express 3.0 x16 slots, ten SATA-600 ports, eight USB 3.0 ports, three USB 3.1 ports, a SATA Express connector, and a high-end audio codec. Let’s take a good look at this board.
The Intel X99 platform supports the new socket LGA2011-v3 processors. However, it is not compatible with former socket LGA2011 CPUs, which require motherboards based on the Intel X79 chipset. The main difference between the two platforms is that LGA2011 processors are compatible with DDR3 memories, while LGA2011-v3 CPUs can use the new DDR4 standard.
The main differences between the X99 and the X79 chipsets, besides the CPU support as mentioned above, are the number of USB 3.0 and SATA-600 ports: the X99 offers ten SATA-600 and six USB 3.0 ports, while the X79 supports only two SATA-600 ports and has no native support for USB 3.0 ports.
In Figure 1, you see the ASRock X99 Extreme6/3.1 motherboard. It uses the ATX form factor (12 x 9.6 inches or 305 x 244 mm).

ASRock X99 Extreme6/3.1Figure 1: ASRock X99 Extreme6/3.1 motherboard

[nextpage title=”Slots”]
Socket LGA2011-v3 processors have a maximum of 40 or 28 PCI Express 3.0 lanes for video cards, depending on the model. This allows a very high-end configuration for the PCI Express x16 slots when a CPU with 40 lanes is installed, but the exact configuration used will depend on the model of the CPU that will be installed.
The ASRock X99 Extreme6/3.1 comes with three PCI Express 3.0 x16 slots, working at x16/x16/x8 if a 40-lane processor is used, and at x16/x8/x4 if a CPU with 28 lanes is installed. There are also two PCI Express 2.0 x1 slots, and a mini-PCI Express slot.
The motherboard supports SLI and CrossFire arrays with up to three video cards.
There is also an M.2 slot, which is compatible with PCI Express 3.0 x4 and SATA M.2 modules. If a PCI Express x4 M.2 module is installed, the third PCI Express 3.0 x16 will be disabled.

ASRock X99 Extreme6/3.1Figure 2: slots

[nextpage title=”Memory Support”]
Intel socket LGA2011-v3 CPUs have an embedded memory controller, meaning that it is the processor, not the chipset, which defines what memory technologies you can have and the maximum amount of memory that is possible. The motherboard, however, may have a limitation as to how much memory can be installed.
The integrated memory controller from socket LGA2011-v3 processors officially supports DDR4 memories up to 2,133 MHz. According to ASRock, the X99 Extreme6/3.1 supports memories up to 3,200 MHz.
One of the most important features of the socket LGA2011-v3 processors is the support for the quad-channel memory architecture, which allows the memory to be accessed in 256-bit mode for higher performance. Since each memory module is a 64-bit entity, four memory modules are needed to enable this architecture. If only two or three memory modules are installed, the memory will be accessed under dual- or triple-channel architecture, respectively.
The ASRock X99 Extreme6/3.1 has eight memory sockets (four at each side of the CPU socket) and you can have up to 128 GiB with this motherboard if you use eight 16 GiB modules.
In order to enable the quad-channel mode, you must install four or eight identical memory modules. If you are installing four modules, you must install them on the black sockets to achieve maximum performance.

ASRock X99 Extreme6/3.1Figure 3: Memory sockets; install four or eight modules for the best performance

[nextpage title=”On Board Peripherals”]
The Intel X99 chipset is a single-chip solution, which is also known as a PCH (Platform Controller Hub). This chip supports ten SATA-600 ports (there are no SATA-300 ports), supporting RAID (0, 1, 10, and 5).
The ASRock X99 Extreme6/3.1 offers those ten SATA-600 ports (one of them shared with an eSATA connector at the rear panel, and another port shared with the M.2 slot). All SATA ports are located at the motherboard’s edge and rotated 90 degrees, so that video cards will not block them. Two SATA-600 ports are shared with a SATA Express connector.

ASRock X99 Extreme6/3.1Figure 4: SATA-600 ports

The Intel X99 chipset supports eight USB 2.0 ports and six USB 3.0 ports. The ASRock X99 Extreme6/3.1 offers seven USB 2.0 ports, two soldered on the rear panel and five available through two headers and one type A connector, located on the motherboard. The motherboard offers eight USB 3.0 ports, four soldered on the motherboard rear panel (using one ASMedia ASM1074 chip to double two USB 3.0 ports controlled by the chipset) and four are available through two headers on the motherboard.
The ASrock X99 Extreme6/3.1 also offers one USB 3.1 type C port at the rear panel, controlled by one ASMedia ASM1142 chip. The new type C connector is amazing because, besides being reversible (you can install the connector in any position), it supports video and power connections (it supports up to 100 W of power). So, it will probably become a universal connection standard soon.
The ASRock X99 Extreme6/3.1 does not support FireWire or Thunderbolt ports.
This motherboard supports 7.1+2 audio format, i.e., eight channels plus two independent channels for audio streaming. On this motherboard, the audio is generated by the chipset using the Realtek ALC1150 codec, which is an excellent audio codec, providing 115 dB signal-to-noise ratio for the analog outputs, 104 dB signal-to-noise ratio for the analog inputs, and up to 192 kHz sampling rate for both inputs and outputs, with 24-bit resolution. These specifications are good even for the user who wants to work professionally capturing and editing analog audio (e.g., converting LPs to CDs or MP3, converting VHS to DVDs or any other digital format, etc.).
The analog audio outputs are independent and the motherboard also comes with an on-board optical SPDIF output. However, there is no header where you can install an adapter to have a coaxial SPDIF output or to connect a cable to older video cards that required a physical connection to have audio on their HDMI outputs.
The analog audio outputs are independent only if you use a 5.1 analog speaker set. If you install a 7.1 analog speaker set, you will need to use the “line in” jack. The audio codec is protected from interference with a metallic shield.

ASRock X99 Extreme6/3.1Figure 5: shielded audio codec

The portrayed motherboard has two Gigabit Ethernet ports, one controlled by an Intel i218V chip, and one controlled by an Atheros AR8171 chip.
In Figure 6, you can see the motherboard rear panel, with a PS/2 shared connector for keyboard or mouse, two USB 2.0 ports, a Clear CMOS button, a USB 3.1 type C port, an eSATA-600 port, four USB 3.0 ports, two Gigabit Ethernet ports, one optical SPDIF output, and the analog audio jacks.

ASRock X99 Extreme6/3.1Figure 6: Motherboard rear panel

[nextpage title=”More Features”]
The ASRock X99 Extreme6/3.1 has power and reset buttons, and a two-digit POST status display. Additionally, it has two BIOS chips selectable by a small switch. The motherboard supports installation of a TPM (Trusted Platform Module), which stores encryption keys in order to improve the computer security.

ASRock X99 Extreme6/3.1Figure 7: BIOS chips, buttons, and display

Besides having one USB 3.1 port at its rear panel, this motherboard brings two USB 3.1 type A ports on a PCI Express x4 expansion card, shown in Figure 8. This card uses an ASMedia ASM1142 chip.

ASRock X99 Extreme6/3.1Figure 8: USB 3.1 card

Figure 9 shows the other accessories that come with the motherboard.

ASRock X99 Extreme6/3.1Figure 9: accessories

[nextpage title=”Voltage Regulator”]
The CPU voltage regulator circuit of the ASRock X99 Extreme6/3.1 has 12 phases for the CPU. The voltage regulator is controlled by an Intersil ISL6379 chip, using a digital design. Each phase uses one FDMS3660S (“22CF 07OD”) integrated circuit, which contains both the “high-side” and the “low-side” MOSFETs.

ASRock X99 Extreme6/3.1Figure 10: voltage regulator circuit

The ASRock X99 Extreme6/3.1 uses 12K Platinum electrolytic capacitors from the Japanese maufacturer Nichicon, and 60 A ferrite chokes, which is an excellent configuration.
If you want to learn more about the voltage regulator circuit, please read our tutorial on the subject.
[nextpage title=”Overclocking Options”]
The portrayed motherboard has several overclocking options. Below, we list the most important ones (0.26 BIOS):

  • CPU Base Clock: from 96.00 MHz to 300.00 MHz in 0.1 MHz increments
  • CPU Core Voltage: from 0.800 V to 2.000 V in 0.001 V increments
  • CPU Core Voltage Offset: from -0.500 V to +0.500 V in 0.001 V increments
  • CPU Cache Voltage: from 0.800 V to 2.000 V in 0.001 V increments
  • CPU Cache Voltage Offset: from -0.500 V to +0.500 V in 0.001 V increments
  • System Agent Voltage Offset: from -0.300 V to 0.600 V in 0.001 V increments
  • CPU Input Voltage: from 1.200 V to 2.300 V in 0.010 V increments
  • Memory Voltage: from 1.000 V to 1.800 V in 0.010 V increments
  • Chipset PLL Voltage: from 1.200 V to 1.800 V in 0.10 V increments
  • MEI Voltage: from 0.900 V to 1.500 V in 0.05 V increments
  • Chipset Voltage: from 0.900 V to 1.500 V in 0.025 V increments

ASRock X99 Extreme6/3.1Figure 11: overclocking options

ASRock X99 Extreme6/3.1Figure 12: memory timings adjusts

ASRock X99 Extreme6/3.1Figure 13: voltage options

[nextpage title=”Main Specifications”]
The main specifications for the ASRock X99 Extreme6/3.1 include:

  • Socket: LGA2011-v3
  • Chipset: Intel X99
  • Super I/O: Nuvoton NCT6791D
  • Parallel ATA: none
  • Serial ATA: ten SATA-600 ports controlled by the chipset (RAID 0, 1, 10, and 5)
  • External SATA: one eSATA-600 port at the rear panel (shared with one of the internal SATA-600 ports)
  • USB 2.0: seven USB 2.0 ports, two on the motherboard rear panel and five available through two headers and one type-A connector on the motherboard
  • USB 3.0: eight USB 3.0 ports, four on the motherboard rear panel and four available through two headers on the motherboard, all of them controlled by the chipset, using one ASMedia ASM1074 chip to double the rear panel ports
  • USB 3.1: one type C USB 3.1 port at the rear panel, controlled by one ASMedia ASM1142 chip and two type A USB 3.1 ports on an expansion card, controlled by another ASMedia ASM1142 chip
  • FireWire (IEEE 1394): none
  • Thunderbolt: none
  • On-board video: no
  • On-board audio: produced by the chipset together with a Realtek ALC1150 codec (7.1+2 channels, 24-bit resolution, 192 kHz sampling rate, 115 dB SNR for the outputs, and 104 dB SNR for the inputs), on-board optical SPDIF output
  • On-board LAN: two Gigabit Ethernet ports, one controlled by an Intel i218V chip and one controlled by an Atheros AR8171 chip
  • Wireless LAN: no
  • Buzzer: no
  • Infrared interface: no
  • Power supply required: EPS12V
  • Slots: three PCI Express 3.0/2.0 x16 slots (working at x16/x16/x8 with a 40-lane CPU or at x16/x8/4 with a 28-lane processor), two PCI Express 2.0 x1 slots, one mini-PCI Express slot, and one M.2 PCI Express x4/SATA slot
  • Memory: eight DDR4-DIMM sockets (up to DDR4-3200, 128 GiB maximum)
  • Fan connectors: one four-pin and one tree-pin connectors for the CPU cooler, and one four-pin and three three-pin connectors for auxiliary fans
  • Extra features: support for TPM, two BIOS chips, two-digit POST diagnostics display, and power, reset, and clear CMOS buttons,
  • Number of CDs/DVDs provided: one
  • Programs included: motherboard utilities
  • More Information: https://www.asrock.com/
  • Average price in the U.S.*: USD 300.00

* Researched at Newegg.com on the day we published this article.
[nextpage title=”Conclusions”]
The ASRock X99 Extreme6/3.1 is an excellent motherboard for socket LGA2011-v3 systems; it is robust and very complete. Besides the features offered by the chipset (ten SATA-600 ports and six USB 3.0 ports), which are enough for most users, it brings one SATA Express port and three USB 3.1 ports, which support twice the speed of USB 3.0 ports, including one type C port at the rear panel.
It brings eight memory sockets and three PCI Express 3.0 x16 slots, supporting SLI and CrossFire with up to three video cards, which is also more than most users will need. As an extra, it also brings a POST diagnostics display and on-board power, reset, and clear CMOS buttons.
Other highlights of this motherboard include the audio section, which uses a high-end codec with an outstanding signal-to-noise ratio, the excellent voltage regulator circuit, and an M.2 slot that is compatible with both SATA and PCI Express 3.0 x4 (used by some high-performance SSDs) interfaces.
If you intend to build a robust gaming computer or workstation with an LGA2011-v3 CPU and are looking for an excellent cost/benefit ratio, the ASRock X99 Extreme6/3.1 is an excellent choice.