Storage, sound, and the little things
The UD3's SATA-based storage all resides in the lower-right corner of the board.
Here we find not one, not two, but three SATA Express connectors. All three of these connectors and their six embedded SATA 6Gbps ports are driven by the Z170 chipset—no auxiliary storage controllers herer. All of these ports are right-angled to make cable insertion easier with longer graphics cards installed.
The UD3's next-gen storage support continues with two M.2 slots, one on either side of the primary PCIe x16 slot. The M.2 connector above the primary PCIe x16 slot, labeled M2D, would be where we'd install M.2 SSDs first. The second M.2 slot, labelled M2A, will end up sandwiched between two video cards in multi-GPU setups. Even in a more mundane single-card system, this slot sits under the blower coolers common on many dual-slot graphics cards today. This heat could cause some M.2 SSDs to get too toasty—Samsung's SM951 PCIe SSD already throttles itself even without a graphics card in play, for example.
The M.2 slots accept mini-SSDs up to 80 mm long (commonly referred to as M.2 2280). Both SATA and NVMe SSDs will work here. Gigabyte also supports U.2 NVMe storage devices like Intel's 750 Series SSD with its M.2 to U.2 adapter card, which plugs into an M.2 slot. Gigabyte sells this adapter separately as the GC-M2-U2-MiniSAS.
Both of these next-gen interfaces serve up some impressive numbers. The two Gen3 lanes that feed each SATA Express connector provide up to 16 Gbps per block, while each M.2 slot's four Gen3 lanes are good for up to 32 Gbps.
That said, not all of this storage connectivity can be used at once. The Z170 chipset provides 26 multi-purpose, high-speed I/O lanes that can be shared between different storage ports. That lane-sharing puts some constraints on which ports can be used at the same time. To help explain which ports are unusable in which scenarios, here's a graphical representation of the SATA ports with labels that we'll talk to in the following paragraphs:
Here's how the sharing breaks down. A SATA M.2 SSD installed in the M2A M.2 slot will disable SATA port 0. If you populate the M2D M.2 slot with a SATA-based SSD both SATA port 3 and its accompanying SATA Express port will become unusable.
The situation becomes even more complicated with PCIe SSDs. Since the M2A M.2 slot has its own dedicated PCIe lanes, installing a PCIe SSD in this slot while the controller is in normal mode doesn't cause you to lose any SATA ports. Like the M2D M.2 slot, though, setting the controller to RAID mode and installing a PCIe-based SSD in the bottom M.2 slot will disable SATA port 5 and its corresponding SATA Express port.
A four-lane PCIe-based SSD installed in the M2D M.2 slot will disable all the SATA ports on the bottom row—ports 0 through 3. Enable RAID mode, and you'll lose SATA port 5 and its corresponding SATA Express port, as well. A two-lane PCIe SSD installed in the M2D M.2 slot will disable SATA ports 2 and 3 and the SATA Express port they're embedded in. Enable RAID mode, and you'll lose those two ports along with SATA port 5 and its corresponding SATA Express port.
With those two M.2 slots and the Z170's support for RAID arrays across PCIe SSDs, the UD3 is ready to serve up some impressive storage performance. Unfortunately, the DMI link between the chipset and the processor is the next bottleneck. Despite this link's upgrade to PCIe Gen3 speeds versus the Gen2 speeds used by the DMI2 link of the Z97 chipset, it's still based on just four PCIe lanes, so it has a maximum potential bandwidth of 32 Gbps (4 GBpit'ss). That bandwidth has to be shared between all devices connected to the chipset.
The Z170X-UD3's rear port cluster has something for everyone. Gigabyte includes VGA, DVI, and HDMI 1.4b display outputs on the Z170X-UD3. Those ports are likely only of interest to buyers looking to tap into a Skylake CPU's integrated graphics processor, though. Folks using discrete graphics cards don't have to worry about these onboard display outputs.
Sandwiched between the trio of display outputs, we have both Type-A and Type-C USB 3.1 ports. These ports are powered by the Intel Alpine Ridge USB 3.1 controller, seen in the center of the picture below:
Unlike some of Gigabyte's higher-end boards, the UD3 feeds the Alpine Ridge controller with only two Gen3 PCIe lanes. This endows it with up to 16 Gbps of bandwidth, rather than the 32 Gbps that four Gen3 lanes would provide. The USB 3.1 Gen2 spec tops out at 10Gbps, so the 16Gbps pipe here isn't really a limitation.
The UD3 only provides us with three rear USB 3.0 ports. Thankfully, four more USB 3.0 ports are available from two internal headers. All ports are connected directly to the Z170 chipset.
Two USB 2.0 ports above the lone PS/2 port, round out the USB connectivity found on the rear port cluster. A further four ports are supported via two internal headers.
The Gigabit Ethernet port is powered by Intel's I219-V controller. On top of the normal Intel GigE drivers, Gigabyte bundles the cFosSpeed traffic-shaping software for Windows. This software, like the suite of software provided with Killer's Gigabit Ethernet controllers, performs packet prioritization on the client PC. While this utility is nice in theory, it doesn't help if the network congestion is occurring at some point outside of the PC.
Time for a colorful diagram to graphically tie up all of the words above:
The Z170X-UD3's is fitted with Gigabyte's "Amp-Up" audio implementation. Underneath the gold EMI shield lies a familiar Realtek audio codec, the ALC1150. A Texas Instruments OP1652 dual-channel op-amp and high-end Nippon Chemi-con audio capacitors round out the remaining audio hardware.
The quality of a motherboard's onboard audio isn't determined purely by component selection, however. The quality of the analog signals themselves is just as important. To this end, Gigabyte has physically isolated the audio circuitry and components from the rest of the PCB to minimize interference and provide an environment that's as noise-free as possible.
To highlight the onboard audio, Gigabyte has added orange LED lighting that traces the border of the isolated circuitry. As we've come to expect from Gigabyte's onboard lighting, three modes of operation are available: a solid glow, a pulsing pattern, and a mode that flashes the audio trace path lighting in time with audio piped through the onboard stereo output. The lighting can also be disabled altogether for a less flashy system build.
The UD3's analog audio output was pleasing to my ears. I didn't detect any unwanted noise under a variety of load and idle conditions. There were no pops, no hissing, nothing to disturb the listening experience. That said, audiophiles will still want to use a dedicated sound card. They could also opt for this board's digital S/PDIF output, though the board can't encode multi-channel audio on the fly. As a result, games are limited to stereo output and virtualized surround sound.
The Z170X-UD3 includes a number of welcome builder-friendly perks. First off, in the box we find a high-quality cushioned I/O shield. This not only makes installing the motherboard in a case easier, it also removes one source of sharp edges that your fingers will come in contact with during the build.
Gigabyte also includes a detachable front-panel wiring block with the UD3—a "G-Connector." Asus has long shipped its motherboards with a similar port block, so we're glad to see other companies following its example. We first saw this feature on Gigabyte's high-end Gaming series boards, and I'm very happy to see this plug carried over to the Ultra Durable lineup, especially this mid-range model. The G-Connector makes the finicky job of wiring up the front-panel header much more pleasant. It sure beats fumbling with a flashlight in a dimly-lit case.
To the left of the chipset heatsink are the two SPI flash chips that put the "dual" in Gigabyte's DualBIOS redundant firmware setup. While motherboards may have moved to UEFI-based firmware, it seems the DualBIOS name is here to stay. I guess "DualUEFI" doesn't quite have the same ring to it. Gigabyte's boards have been fitted with backup firmware chips for years, and the Z170X-UD3 carries on that tradition. Directly above the front-panel header is the "clear CMOS" jumper. Just short these two pins together for a few seconds, turn on your system, and your existing firmware configuration will be a thing of the past.
Gigabyte has unfortunately chosen not to endow the UD3 with support for its Q-Flash Plus feature. Although Q-Flash Plus doesn't get used every day, the ability to update a motherboard's firmware with nothing more than a USB thumb drive and a power supply can save you from having to borrow a supported CPU to update the board for a newer chip or to get around some other show-stopping issue.
Unlike some of Gigabyte's top-end motherboards, the UD3 lacks a hardware-based shortcut to enter the firmware. We point this out because with the ultra-fast-boot option enabled, no amount of key-mashing on boot-up will get you into the firmware. Thankfully, there's a software solution via Gigabyte's Fast Boot Windows utility, which has a handy "Enter BIOS Setup Now" button that reboots directly into the UEFI.
Over on the left-hand side of the UD3, we see an interesting mix of old and new. A serial port header comes courtesy of the iTE IT8628E Super I/O controller. To the right of this, we have a connector used by Gigabyte's Thunderbolt add-in card.
Traveling all the way up to the top of the board, we find a handy little two-digit diagnostic display that shows debug codes when the system boots. This readout can be very useful if you're trying to solve issues that occur very early in the boot process. That said, it can get crowded up at of the top corner of the board, so it may be a little difficult to read the display once the system is assembled. Gigabyte details all of the codes this readout can display in section 3-3 of the board's user manual, should you need help figuring out what your own UD3 is trying to tell you when it won't boot.
Now that we've covered the Z170X-UD3 from head-to-toe, let's check out the firmware.