[nextpage title=”Introduction”]

Let’s take a look at the ASRock Fatal1ty X370 Gaming K4, a aminstream motherboard with the AM4 socket, based on the AMD X370 chipset, supporting Ryzen CPUs. Check it out!

The AMD X370 chipset is the high-end model for the AM4 socket, used by the new Ryzen CPUs and the future seventh-gen APUs. The X370 differs from the mid-range chipset for this platform, the B350, by the number of PCI Express 2.0 lanes (eight, against six on the B350), USB 3.0 ports (two on the B350 and six on the X370), and SATA-600 ports (eight on the X370 and six on the B350).

Another difference is that the X370 supports splitting the 16 PCI Express 3.0 lanes on two slots (x8/x8 configuration), which the B350 doesn’t. Both the chipsets support two USB 3.1 ports, and RAID 0, 1, and 10.

You can see the ASRock Fatal1ty X370 Gaming K4 motherboard in Figure 1. It uses the ATX form factor, measuring 12” x 9.6” (305 x 244 mm).

ASRock Fatal1ty X370 Gaming K4Figure 1: ASRock Fatal1ty X370 Gaming K4 motherboard

[nextpage title=”Slots”]

It is important to keep in mind that, at AM4 platform, only the PCI Express lanes controlled by the CPU (24 on total, 16 for the video card(s), four for an M.2 slot and four for the communication with the chipset) are PCI Express 3.0; the PCI Express lanes controlled by the chipset are use the 2.0 standard.

The ASRock Fatal1ty X370 Gaming K4 comes with two PCI Express 3.0 x16 slots and four PCI Express 2.0 x1 slots.

The PCI Express 3.0 x16 slots share the same 16 lanes, so they can work at x16/x0 (if the second one is unused) or x8/x8 configurations.

There are also two M.2 slots, the first one supporting both PCI Express 3.0 x4 and SATA-600 SSDs, and the second one supporting SATA-600 and PCI Express 2.0 x2 devices.

There is a third M.2 slot, supporting 2230 Wi-Fi cards.

The motherboard supports CrossFire and SLI with up to two video cards.

The two PCI Express x16 slots are covered by stainless steel shields, that work as a shield against interference, and also improving mechanical strength of each slot.

ASRock Fatal1ty X370 Gaming K4Figure 2: slots

[nextpage title=”Memory Support”]

AMD CPUs have an embedded memory controller, meaning that it is the processor, not the chipset, that 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.

AM4 CPUs are compatible with DDR4 (up to 2,667 MHz, depending on the modules configuration) memory. According to ASRock, the Fatal1ty X370 Gaming K4 supports DDR4 memories up to 2,933 MHz.

The ASRock Fatal1ty X370 Gaming K4 has four memory sockets. You can install up to 64 GiB with this motherboard if you use four 16 GiB modules.

In order to enable the dual-channel mode, you must install two or four memory modules. When installing two memory modules, use the first and third memory slots to enable dual-channel mode.

ASRock Fatal1ty X370 Gaming K4Figure 3: memory sockets; install two or four modules for the best performance

[nextpage title=”On Board Peripherals”]

The AMD X370 chipset is a single-chip solution. This chip offers eight SATA-600 ports, supporting RAID (0, 1, and 10). The motherboard comes with six SATA-600 ports, and the other two ones are used by the M.2 slots.

ASRock Fatal1ty X370 Gaming K4Figure 4: the ten SATA-600 ports

The AMD X370 chipset supports six USB 2.0 ports, six USB 3.0 (also called USB 3.1 Gen1) ports, and two USB 3.1 Gen2 ports. There are also four USB 3.0 ports controlled by the CPU.

The ASRock Fatal1ty X370 Gaming K4 offers four USB 2.0 ports, available through two headers located on the motherboard. There are ten USB 3.0 ports, six on the rear panel and four available through two headers. There are also two USB 3.1 ports, one Type A and one Type C.

The ASRock Fatal1ty X370 Gaming K4 does not support FireWire or Thunderbolt ports.

This motherboard comes with a high-end audio circuit. It uses a shielded Realtek ALC1220 codec, which offers 7.1 audio with a 120 dBA signal-to-noise ratio at the analog outputs. Unfortunately, no more specs of this codec are available. All the audio section is physically separated from the other circuitry by a line that reduces the interference and helps the audio section to achieve its nominal signal-to-noise ratios. All the capacitors on this circuit are audio models from Japanese manufacturer Nichicon. The analog audio outputs are independent and use gold-plated connectors. The motherboard also comes with an on-board optical SPDIF output.

The audio section of the Fatal1ty X370 Gaming K4 also uses a TI NE5532 amplifer for headphones. Figure 5 shows the audio section of the motherboard, without its plastic cover.

ASRock Fatal1ty X370 Gaming K4Figure 5: audio section

The portrayed motherboard has one Gigabit Ethernet port, controlled by an Intel i211AT chip.

In Figure 6, you can see the motherboard rear panel with room for two Wi-Fi antennas,  PS/2 keyboard and mouse connectors, HDMI connector, four USB 3.0 ports, two USB 3.1 ports (one Type A and one Type C,)  two more USB 3.0 ports, a Gigabit Ethernet port, optical SPDIF output, and the analog audio jacks.

Notice that this motherboard has a video output, to be used with the future AM4 processors with integrated video. With a Ryzen CPU, however, you will not be able to use this feature.

ASRock Fatal1ty X370 Gaming K4Figure 6: motherboard rear panel

The ASRock Fatal1ty X370 Gaming K4 has RGB LEDs around the chipset heatsink. There are connectors for RGB ribbons and coolers.

The motherboard has a two-digit display that informs the POST error code.

ASRock Fatal1ty X370 Gaming K4Figure 7: POST error code display

In Figure 8, you can see the accessories that come with the ASRock Fatal1ty X370 Gaming K4.

ASRock Fatal1ty X370 Gaming K4Figure 8: accessories

[nextpage title=”Voltage Regulator”]

The ASRock Fatal1ty X370 Gaming K4 uses a 12-phase CPU voltage regulator circuit for the CPU. The voltage regulator uses an IR35201 controller chip (digital design). Each phase uses one SM4336NSKP (SM4336) and one SM4337NSKP (SM4336) transistors.

This circuit is shown in Figure 9.

ASRock Fatal1ty X370 Gaming K4Figure 9: voltage regulator circuit

The ASRock Fatal1ty X370 Gaming K4 uses “12K Black” Japanese solid capacitors. All coils on this motherboard are ferrite ones with 45A specification.

If you want to learn more about the voltage regulator circuit, please read our tutorial on the subject.

[nextpage title=”Main Specifications”]

The main specifications for the ASRock Fatal1ty X370 Gaming K4 include:

  • Socket: AM4
  • Chipset: AMD X370
  • Super I/O: Nuvoton NCT6779D
  • Parallel ATA: none
  • Serial ATA: six SATA-600 ports, controlled by the chipset (RAID 0, 1, and 10)
  • External SATA: none
  • USB 2.0: four USB 2.0 ports, available through two headers on the motherboard
  • USB 3.0 (USB 3.1 Gen1): ten USB 3.0 ports, six on the motherboard rear panel and four available through two headers
  • USB 3.1 (USB 3.1 Gen2): two USB 3.1 ports, one Type A and one Type C, controlled by the chipset
  • FireWire (IEEE 1394): none
  • Thunderbolt: none
  • On-board video: HDMI output (produced by the CPU, if available)
  • On-board audio: Produced by a Realtek ALC1220 codec (7.1 channels, 120 dB SNR for the outputs, no mode info available)
  • On-board LAN: one Gigabit Ethernet port, controlled by an Intel i211AT chip
  • Buzzer: no
  • Infrared interface: no
  • Power supply required: EPS12V
  • Slots: two PCI Express 3.0 x16 slots (working at x16/0 or x8/x8), four PCI Express 2.0 x1 slots, one M.2 slot compatible with PCI Express 3.0 x4 and SATA-600 SSDs, and one M.2 slot compatible with PCI Express 2.0 x2 and SATA-600.
  • Memory: four DDR4-DIMM sockets (up to DDR4-2933, 64 GiB maximum)
  • Fan connectors: two four-pin connector for the CPU cooler, and three four-pin connector for auxiliary fans
  • Extra features: RGB LED lights, POST error display
  • Number of CDs/DVDs provided: one
  • Programs included: motherboard utilities and drivers
  • More Information: http://www.asrock.com
  • Average Price in the U.S.*: USD 155.00

* Researched at Newegg.com on the day we published this article.

[nextpage title=”Conclusions”]The ASRock Fatal1ty X370 Gaming K4 is a complete motherboard for Ryzen CPUs. It is basically a budget version of the X370 Taichi, which is a high-end motherboard. The only points where it is behind the X370 Taichi are the number of SATA-600 ports (six on the Gaming K4, ten on the Taichi) and the voltage regulator, that brings 16 phases on the Taichi and 12 phases on the X370 Gaming K4.

Besides that, it brings all the features offered by the high-end chipset for the AM4 platform (the X370), like the ten USB 3.0 ports, two USB 3.1 ports, eight SATA-600 ports (two of them available on the M.2 slots), and the compatibility with SLI and CrossFire with two video cards.

The motherboard has a high-end audio section and it will satisfy even the more demanding users, with its high-definition codec, gold plated analog connectors, and headphone amplifer.

For all of this, the ASRock Fatal1ty X370 Gaming K4 is a motherboard with great cost/benefit ratio if you are building a computer using a Ryzen CPU.