Gigabyte also pays special attention to the growing market of Mini-ITX systems. They try to offer products in this form-factor for all current processors. The Lynx platform also wasn’t an exception, but for some reason this compact Socket FM1 mainboard is positioned as a solution for developing markets only and is not available in the USA. As a result, Gigabyte A75N-USB3 is a very rare product, which you won’t often see in stores. I have to say that it is a real pity, because it is very well built and has great functionality and could obviously become popular otherwise.
Gigabyte engineers used their own approach to designing their Mini-ITX mainboard. Unlike products from Asus and Zotac, Gigabyte A75N-USB3 is relatively simple and therefore quite affordable in terms of price. However, the quality of the board didn’t suffer in any way and the board looks very well-built. We can’t complain about the functionality either. Gigabyte A75N-USB3 has everything a contemporary compact system may need due to the advanced A75 chipset it is based on.
In fact, it is that chipset that provides the mainboard with support of contemporary SATA 6 Gbps and USB 3.0 interfaces. Gigabyte engineers allocated the ports in the chipset in the following way. Four SATA-600 ports are laid out on the mainboard itself and an additional SATA ports is located on the mainboard back panel as an eSATA connector. Together with this connector the back panel has all USB 3.0 ports the chipset has to offer (a total of four) and two USB 2.0 ports laid out as an onboard pin-connector. Unfortunately, in this case there is no way to allocate any of the USB 3.0 ports for the system case front panel, but many mainboard have the same exact issue these days. Besides, there aren’t that many Mini-ITX system cases yet that could boast USB 3.0 ports in the front anyway.
The back panel of Gigabyte A75N-USB3 doesn’t boast a variety of ports as well. Besides the above mentioned six USB ports and eSATA connector, there are three analog audio-jacks, an SPDIF out, a Gigabit network port and two monitor/TV-set outs. The network controller is implemented with a Realtek RTL8111E controller, and sound is provided by the eight-channel Realtek ALC889 controller, which offers a slightly better SNR than the other controller modifications.
Note that the mainboard allows connecting monitors as well as TV-sets using digital interface exclusively. It has only two Outs: HDMI and DVI-D, which is incompatible with D-Sub adapters. Moreover, in both cases the maximum supports screen resolution will be only 1920x1200.
The PCB layout of Gigabyte A75N-USB3 is probably the best of all four mainboards reviewed today. There are no components on the back of the PCB, and all slots and connectors are located in traditionally convenient and easy to reach spots. However, I have to admit that I am a little concerned about the distance between the processor socket and the PCI Express x16 slot. It is bigger than on Asus F1A75-I Deluxe, and the cooler retention on A75N-USB3 has been rotated by 90 degrees, but some low-profiles coolers, like Scythe Big Shuriken 2, for example, may prevent you from using an external graphics card on this mainboard.
The manufacturer classifies Gigabyte A75N-USB3 as Ultra Durable 3 mainboard, which means that the board meets specific quality standards and uses 2 oz copper PCB. The processor voltage regulator circuitry on this mainboard is also not a primitive one and uses combination DrMOS modules and has four phases. As a result, even though there is no cooling on the voltage regulator components, Gigabyte promises that their A75N-USB3 not only will be fully compatible with the entire range of Socket FM1 processors including 65 W and 100 W models, but also will remain stable during overclocking.
However, the one-chip chipset does have a heatsink. And even though it is only a not very intimidating low-profile aluminum plate, we didn’t detect any overheating issues during work: the heat dissipation of the A75 chip doesn’t exceed 8 W. the mainboard has two fan connectors : one four-pin connector for the processor cooling fan and another three-pin connector for a case fan. The mainboard is capable of adjusting only the CPU fan rotation speed, but is may be done via PWM as well as voltage control.
Gigabyte A75N-USB3 comes with a set of primitive accessories. Besides the mainboard itself there is a disk with the software and drivers, a user manual, an I/O Shield for the back panel and two SATA cables.
While most mainboard makers have long been using BIOS with graphics interface, a number of Gigabyte products continue to come out featuring old-school BIOS with text interface. Gigabyte A75N-USB3 is one of them. Luckily, it doesn’t affect the functionality that much. This BIOS has everything necessary for proper configuring of multipliers, frequencies and voltages.
Besides special overclocking-friendly functions, the BIOS of Gigabyte A75N-USB3 also allows to lower the frequencies and voltages below their nominal values. The low-voltage memory is also fully supported.
During our overclocking experiments, Gigabyte A75N-USB3 proves capable of working in non-nominal modes. Even when the clock generator frequency was significantly increased, we didn’t experience any issues with the monitor outs, or functioning of the SATA interface in AHCI mode. This is a very good indication not only for a Mini-ITX mainboard, but for any Docket FM1 mainboard in general. However, a special setting we dug out in the heart of the BIOS that should allegedly allow us to independently overclock the graphics core (like the one we have just seen by the ASRock board) didn’t work. GPU frequency in Llano processors increases only when the BCLK frequency does, and there is no other way.