Storage, ports and audio
The Impact's SATA ports reside in the bottom right corner of the board, between the chipset heatsink and the DIMM slots.
Here we find four standard SATA 6Gbps ports. Given that the board will most likely be installed in small Mini-ITX enclosures, four SATA ports seems ample. Asus decided to eschew any support for SATA Express on the Impact. That omission is no great loss, considering how few drives on the market support the standard. Instead, the Maximus VIII Impact puts all its next-gen storage eggs in the NVMe basket with a single U.2 connector on the other side of the board.
The U.2 connector is normally sandwiched between the Wi-Fi card and the audio riser. Removing the SupremeFX audio card, we get a much better look at this next-gen storage goodness. PCIe SSDs connected via this interface, like Intel's 750 Series SSD, get four Gen3 lanes from the chipset. Those lanes give PCIe storage devices up to 32 Gb/s (4 GB/s) of bandwidth, an impressive increase over their SATA-based counterparts.
Despite the board space it saves, the U.2 connector is a bit of an odd duck in the world of storage devices right now. It would have been nice if the Maximus VIII Impact came bundled with a U.2 to an M.2 adapter so that owners could use more common M.2 PCIe SSDs in the near term. U.2 devices are often 2.5" SSDs that need bulky cabling and a dedicated drive bay. Both of those demands can be liabilities in Mini-ITX cases, and gumstick M.2 SSDs sidestep them entirely.
A welcome side effect of the limited expansion options forced by the Impact's diminutive board dimensions is that there are no pesky "sharing" rules that place restrictions on which storage ports can be used simultaneously. What you see is what you get.
With the audio riser removed, we can also see the board's eight voltage monitoring points below the U.2 connector. Asus' engineers are using almost every square millimeter of board real estate. Hopefully those who would use these voltage monitoring points aren't going to be needing audio.
Just to the right of the U.2 connector we can see the Impact's socketed firmware chip. Slightly above and to the right is a two-pin header that connects to the CMOS battery. Previous iterations of the Impact board had the CMOS battery mounted vertically on the board's surface. Presumably, moving the CMOS battery off the board itself freed up valuable PCB space for other components. Once again, it's impressive how much functionality Asus crammed into just under 45 square inches.
One area where the Maximus VIII Impact has been forced to go on a diet is in the fan header department. The board itself supports just two fan headers: one CPU, and one system. Enthusiast-class Mini-ITX systems often require more than just one system fan header, though. To solve this problem, Asus bundles one of its fan extension cards with the board.
This extension module connects to the EXT_FAN header on the top-left corner of the Impact, and it provides three more four-pin fan headers and three more connectors for standard temperature probes. Thermistors attached to the fan module supply reference temperatures to the fan control intelligence managed by the board's firmware and utility software. This bumps the number of temperature-controlled fan headers that the board can support to five. A very respectable number, even by full-sized ATX standards.
The Maximus VIII Impact's rear port cluster is part control panel, part I/O. Starting at the left, we have S/PDIF audio output. This port passes a pristine digital signal to compatible speakers and receivers, neatly bypassing the pitfalls associated with onboard analog audio. The digital out natively supports stereo playback and surround-sound sources like movies with pre-encoded tracks. Bundled DTS Connect software adds on-the-fly encoding for multi-channel output, allowing surround-sound game audio to be piped through the S/PDIF out, as well.
For tapping into Skylake's integrated GPU, the Impact offers a single HDMI 1.4b connector, thanks to an ASMedia ASM1442K level shifter. Folks with discrete graphics cards don't have to concern themselves with the onboard display outputs, of course.
A small vertical riser provides a handful of buttons and a two-digit diagnostic display. Asus calls this the Impact Control module. The top-most square button restores firmware defaults. The square button below is for Asus' USB BIOS Flashback feature. The orange button powers on the system, while the black one resets it. Having these functions accessible outside the case is a huge bonus for Mini-ITX systems, whose internals are often too crowded to poke around inside easily.
A stack of four USB 3.0 ports, in blue, are connected directly to the chipset. The Impact also provides two more USB 3.0 ports from an internal header. The bottom-most port is the one that you'll need to connect your keyboard to in order to use Asus' KeyBot functionality. KeyBot allows you to configure and assign macros to specific keys and pre-record sequences of characters for immediate play back on a single key press. You can also assign hotkeys for tasks like powering on, clearing the CMOS, booting directly to the firmware, and more. The KeyBot software works in conjunction with onboard hardware to make this possible.
The USB 3.0 port second from the bottom is used for the USB BIOS Flashback functionality. This feature lets one update the firmware with nothing more than a USB thumb drive and a power supply. Although it's not a feature you'll use every day, BIOS Flashback could save you from having to beg, borrow, or steal a supported CPU to flash the firmware for a newer chip.
To the right of the USB 3.0 port stack are the connectors for the wireless antenna. Wi-Fi connectivity is provided by a Qualcomm Atheros QCA61x4A 802.11ac controller with a 2x2 antenna and dual-band support for 2.4GHz and 5GHz networks alike. This chip supports Multi-User MIMO (MU-MIMO) and Bluetooth 4.1. The Wi-Fi adapter itself is an M.2 2230 card that connects to the board with a vertical M.2 slot adjacent to the USB stack.
The Gigabit Ethernet port is powered by Intel's I219-V controller. Below this port are USB 3.1 Type-A and Type-C ports, powered by the onboard Alpine Ridge USB controller.
We generally expect motherboard makers to ship a cushioned I/O shield with their high-end products, and Asus doesn't disappoint on this front. In the Impact's box, we get a nicely cushioned I/O shield. Our Band-Aids can safely stay in the medicine cabinet today.
After all those words, it's time to break out the crayons for a graphical representation of the Maximus VIII Impact's port cluster:
Similar to previous Maximus Impact boards, analog audio is handled on an entirely separate audio riser, which Asus calls the "SupremeFX Impact III." This card gets the sensitive analog signals and components off the main PCB, away from the electrically noisy environment below. EMI shielding around the audio board could help matters even more. The SupremeFX Impact III is something of a hybrid between a discrete sound card and a more traditional integrated audio implementation, where all the components are on the motherboard PCB.
Those three audio jacks have a little something extra up their sleeves. Each one is back-lit with a different colored LED: red for microphone in, green for line out, and blue for line-in. This can help you identify which output is which in the dark. It also looks pretty cool.
At the heart of the Impact's audio implementation is Realtek's familiar ALC1150 codec, backed up by premium audio components. Moving left, we can see high-end Nichicon SW series capacitors, an ESS Sabre ES9023P DAC, a Texas Instruments RC4580 headphone amplifier, a dedicated high-precision clock generator, and an NEC de-pop relay. The headphone amp is rated for headphones up to 600 ohms, and it automatically detects headphone impedance. That should cover most common audio headgear.
This audio hardware is paired with Asus' own Sonic Studio and Sonic Radar software. Sonic Studio is similar to the Nahimic software that we looked at in the MSI Z170A Gaming M5 review. It provides virtual surround support, a handful of tunable audio effects and an equalizer, as well as some default profiles for music, movies, and gaming.
Sonic Studio also has options for tuning incoming and outgoing microphone feeds, and it can route a recording or streaming session through its software stack.
Sonic Radar is an Asus-developed application that provides a visual representation of surround-sound game audio. It provides an overlay that shows the direction in-game sounds are coming from. The overlay itself is highly configurable with adjustable opacity, size, and positioning.
Sonic Radar's different filtering modes allow you to focus on specific kinds of sounds: gunshots, explosions, voices, etc. Settings can be toggled using either the application itself, or via hotkeys.
My ears were happy during our audio testing. The analog output didn't produce any unwanted feedback or noise with the system at idle or under load. That's a good thing, because we'd have to resort to a USB sound card or another external solution if the Impact's onboard audio wasn't up to snuff.