ASUS Z87-A Motherboard

[nextpage title=”Introduction”]

The ASUS Z87-A is a mid-range socket LGA1150 motherboard targeted for the “Haswell” processors (fourth-generation Core i3, Core i5, and Core i7 processors), debuting at a very affordable price. Let’s see what this motherboard has to offer.

The new Intel Z87 chipset provides two important upgrades compared to its predecessor, the Z77: six USB 3.0 ports instead of four and six SATA-600 ports instead of only two. Another important difference between the two chipsets is where the video outputs of the motherboard are connected. While with both chipsets the video is generated by the CPU, on the Z77 the video signal was routed to the chipset, and the video outputs were connected to the chipset. On the Z87 chipset, the video outputs are connected directly to the processor. Both chipsets support up to three independent video monitors. The Z87 supports all other features provided by the Z77, such as Smart Response (installing an SSD as a cache for the main hard drive), Smart Connect (allowing the computer to receive emails and refresh webpages while it is in sleep mode), and Rapid Start (faster boot times) technologies.

You can see the ASUS Z87-A motherboard in Figure 1.

Figure 1: ASUS Z87-A motherboard

[nextpage title=”Slots”]

The ASUS Z87-A comes with two PCI Express 3.0 x16 slots, one PCI Express 2.0 x16 slot (working at x2 speed), two PCI Express 2.0 x1 slots, and two standard PCI slots.

The two PCI Express 3.0 x16 slots are controlled by the CPU, with the first slot working at x16 when only one video card is installed, and with both working at x8 when two video cards are installed.

The third PCI Express x16 slot is 2.0 and works at x2 (yes, you read it right). If you plan to install a dual-slot video card in this slot, you will have to buy a case with at least eight slots. (Computer cases usually have seven.)

The PCI Express 3.0 x16 slots support both SLI and CrossFireX technologies. It is important to note that, according to the motherboard’s manual, the PCI Express 2.0 x16 slot doesn’t support these technologies and can’t be used to install a third video card under SLI or CrossFireX modes.

Since the Intel Z87 chipset doesn’t support standard PCI slots, the motherboard uses an ASMedia ASM1083 bridge chip to connect the standard PCI slot to a PCI Express x1 lane.

Figure 2: Slots

[nextpage title=”Memory Support”]

Intel socket LGA1150 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.

The integrated memory controller from socket LGA1150 processors supports DDR3 memories up to 1,600 MHz. According to ASUS, the Z87-A supports memories up to 2,800 MHz.

The ASUS Z87-A has four memory sockets. Since DDR3 memory modules can be found in capacities up to 8 GiB, you can have up to 32 GiB with this motherboard if you use four 8 GiB modules.

In order to enable the dual-channel mode, you must install two or four memory modules. On the ASUS Z87-A, the first and third memory sockets are yellow, while the second and fourth are black. When installing two memory modules, use the yellow sockets.

Figure 3: Memory sockets; install two or four modules for the best performance

[nextpage title=”On Board Peripherals”]

The Intel Z87 chipset is a single-chip solution, which is also known as a PCH (Platform Controller Hub). This chip has six SATA-600 ports, supporting RAID (0, 1, 10, and 5). This motherboard doesn’t have any additional SATA ports. The SATA ports are installed on the motherboard edge and rotated 90°, so the installation of video cards won’t block them.

Figure 4: The six SATA-600 ports controlled by the chipset

The Intel Z87 chipset supports 14 USB 2.0 ports and six USB 3.0 ports. The ASUS Z87-A offers eight USB 2.0 ports, two located on the motherboard rear panel and six available through three headers located on the motherboard, and six USB 3.0 ports, four available on the motherboard rear panel and two available through a header.

The ASUS Z87-A doesn’t support FireWire 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 ALC892 codec, which is a decent audio codec for the average user, providing 97 dB signal-to-noise ratio for the analog outputs, 90 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 for the average user, but if you want 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.), you should pick a motherboard with a codec that offers a signal-to-noise ratio of at least 97 dB SNR at its analog input.

The analog audio outputs are independent and the motherboard also comes with an on-board optical SPDIF output. It also has a two-pin header labeled “SPDIF_OUT”, 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 portrayed motherboard has one Gigabit Ethernet port, controlled by a Realtek RTL8111GR chip.

In Figure 5, you can see the motherboard rear panel with a shared PS/2 connector for keyboard and mouse, two USB 2.0 ports, Mini DisplayPort output, optical SPDIF output, HDMI output, VGA output, DVI-D output, four USB 3.0 ports, one Gigabit Ethernet port, and the analog audio jacks.

Figure 5: Motherboard rear panel

[nextpage title=”Other Features”]

The “MemOK!” button, shown in Figure 6, allows you to test the compatibility of the memory modules that are installed.

Figure 6: MemOK! button

A button called “DirectKey,” which is located next to the PCI Express 2.0 x16 slot, allows you to enter directly on the motherboard setup program.

The ASUS Z87-A comes with the “TPU” and “EPU” switches (see Figure 4). The “TPU” switch enables automatic overclocking, while the “EPU” switch allows the motherboard to reduce the CPU voltages while it is idle in order to save energy.

The portrayed motherboard supports the installation of a TPM (Trusted Platform Module), in charge of storing encryption keys in order to increase the security of the computer. The motherboard also has a legacy serial port, available through a header labeled “COM,” but it doesn’t come with the necessary adapter.

In Figure 7, you can see all of the accessories that come with the ASUS Z87-A.

Figure 7: Accessories

[nextpage title=”Voltage Regulator”]

The CPU voltage regulator circuit of the ASUS Z87-A has eight phases for the CPU. The voltage regulator is controlled by ASUS DIGI+ ASP1251 chip, which uses a digital design. Each phase is driven by two NTMFS4937N MOSFETs, which provide a maximum RDS(on) of 6 mΩ.

Figure 8: Voltage regulator circuit

The ASUS Z87-A uses solid capacitors and ferrite-core coils. If you want to learn more about the voltage regulator circuit, please read our tutorial on the subject.

[nextpage title=”Overclocking Options”]

The ASUS Z87-A has several overclocking options. Below, we list the most important ones:

• CPU Base Clock: From  60.0 MHz to 300.0 MHz in 0.1 MHz increments
• Memory Frequency: From 800 MHz to 3200 MHz in 266 MHz increments
• CPU Fixed Frequency: From 300 kHz to 1000 kHz in 50 kHz increments
• CPU Core Voltage: From 0.001V to 1.920V  in 0.001V increments
• CPU Cache Voltage: From 0.001V to 1.920V in 0.001V increments
• CPU System Agent Voltage: From 0.001V to 0.999V in 0.001V increments
• CPU Analog I/O Voltage: From 0.001V to 0.999V in 0.001V increments
• CPU Digital I/O Voltage: From 0.001V to 0.999V in 0.001V increments
• Chipset (PCH VLX) Voltage: From 0.8000V to 2.0000V in 0.00625V increments
• Memory Voltage: From 1.20000V to 2.40000V in 0.005V increments
• Memory Termination Voltage (VTTDDR): From 0.6000V to 1.4000V in 0.00625V increments
• Memory Reference Voltage: From 0.39500x to 0.63000x in 0.00500x increments

Figure 9: Overclocking options

Figure 10: Voltage options

Figure 11: Voltage options

[nextpage title=”Main Specifications”]

The main specifications for the ASUS Z87-A include:

• Socket: LGA1150
• Chipset: Intel Z87 Express
• Super I/O: Nuvoton NCT6791D
• Parallel ATA: None
• Serial ATA: Six SATA-600 ports controlled by the chipset (RAID 0, 1, 10, and 5)
• External SATA: None
• USB 2.0: Eight USB 2.0 ports, two on the motherboard real panel and six available through three headers on the motherboard
• USB 3.0: Six USB 3.0 ports, four on the motherboard rear panel and two available through one header on the motherboardFireWire (IEEE 1394): None
• Thunderbolt: None
• On-board video: Controlled by the CPU; Mini DisplayPort, HDMI, DVI-D, and VGA connectors
• On-board audio: Produced by the chipset together with a Realtek ALC892 codec (7.1+2 channels, 24-bit resolution, 192 kHz sampling rate, 97 dB SNR for the outputs, and 90 dB SNR for the inputs), on-board optical SPDIF output
• On-board LAN: One Gigabit Ethernet port controlled by a Realtek RTL8111GR chip
• Buzzer: No
• Infrared interface: No
• Power supply required: EPS12V
• Slots: Two PCI Express 3.0/2.0 x16 slots (working at x16/x0 or x8/x8), one PCI Express 2.0 x16 slot (working at x2), two PCI Express 2.0 x1 slots, and two PCI slots (ASMedia ASM1083 bridge chip)
• Memory: Four DDR3-DIMM sockets (up to DDR3-2800, 32 GiB maximum)
• Fan connectors: One four-pin connector for the CPU cooler and four four-pin connectors for auxiliary fans
• Extra features: “TPU” switch, “EPU” switch, Legacy serial port, and support for TPM
• Number of CDs/DVDs provided: One
• Programs included: Motherboard utilities
• More Information: https://www.asus.com
• MSRP in the U.S.: USD 150

[nextpage title=”Conclusions”]

The ASUS Z87-A is a motherboard targeted to the average user who is building a mid-range computer using one of the new “Haswell” CPUs (fourth-generation Core i3, Core i5, or Core i7 processors).

The highlights of this motherboard include the presence of six USB 3.0 ports, six SATA-600 ports, two PCI Express 3.0 x16 slots, a good voltage regulator circuit, and more. The audio codec used is more than adequate for the average user.

There is, however, one drawback with this motherboard, but it shouldn’t affect most users. It is regarding the PCI Express 2.0 x16 slot, which works at x2 speed and you can’t use it with SLI and CrossFireX configurations, rendering it pretty much useless.