Table of Contents
The ASUS Republic of Gamers (ROG) line of motherboards, both Maximus and Rampage, are known for being some of the best overclocking boards out there. Their newest ITX iteration, the Maximus VIII Impact, is on the test bed for this review. If past experience is any indication, then the Maximus VIII Impact should be packed with features despite its small form factor. Let’s see what it brings to the table.
Specifications & Features
(Courtesy of ASUS)
|ASUS Maximus VIII Impact Specifications|
|CPU||Intel® Socket 1151 for 6th Generation Core™ i7/Core™ i5/Core™ i3/Pentium®/Celeron® Processors|
Supports Intel® 14 nm CPU
Supports Intel® Turbo Boost Technology 2.0
* The Intel® Turbo Boost Technology 2.0 support depends on the CPU types.
* Refer to www.asus.com for CPU support list
|Memory||2 x DIMM, Max. 32GB, DDR4 4133(O.C.)/4000(O.C.)/3866(O.C.)/3800(O.C.)/3733(O.C.)/3600(O.C.)/3500(O.C.)/3466(O.C.)/3400(O.C.)/3333(O.C.)/3300(O.C.)/3200(O.C.)/3000(O.C.)/2800(O.C.)/2666(O.C.)/2400(O.C.)/2133 MHz Non-ECC, Un-buffered Memory|
Dual Channel Memory Architecture
Supports Intel® Extreme Memory Profile (XMP)
* Hyper DIMM support is subject to the physical characteristics of individual CPUs.
* Refer to www.asus.com for the Memory QVL (Qualified Vendors Lists).
|Onboard Graphics||Integrated Graphics Processor- Intel® HD Graphics support|
– Supports HDMI with max. resolution 4096 x 2160 @ 24 Hz
Supports Intel® InTru™ 3D, Quick Sync Video, Clear Video HD Technology, Insider™
|Expansion Slot||1 x PCIe 3.0/2.0 x16 (x16 mode, black)|
|Storage||Intel® Z170 chipset: |
1 x U.2 port, black,
4 x SATA 6Gb/s port(s), gray,
Support Raid 0, 1, 5, 10
Intel® Rapid Storage Technology supports*1
Supports Intel® Smart Response Technology*1
|LAN||Intel® I219V, 1 x Gigabit LAN Controller(s), GameFirst technology|
Intel® LAN- Dual interconnect between the Integrated LAN controller and Physical Layer (PHY)
|Wireless Data Network||Wi-Fi 802.11 a/b/g/n/ac|
Supports dual band frequency 2.4/5 GHz
|Audio||ROG SupremeFX Impact III 5.1-channel High Definition Audio CODEC|
– Supports : Jack-detection, Multi-streaming, Front Panel Jack-retasking
– SupremeFX Shielding Technology
– ESS® ES9023P DAC: dB SNR, dB THD+N (Max. kHz/ -bit)
– 2VRMS Headphone Amp into (32-600Ohms)
– Front panel audio connector (AAFP)
– Gold-plated jacks
– DTS Connect
– Optical S/PDIF out port(s) at back panel
– Sonic SenseAmp
– Sonic Studio II
– Sonic Radar II
|USB Ports||Intel® Z170 chipset:|
6 x USB 3.0 port(s) (4 at back panel, blue, 2 at mid-board)
Intel® USB 3.1 controller:
1 x USB 3.1 port(s) (1 at back panel, black, Type-C)
Intel® USB 3.1 controller:
1 x USB 3.1 port(s) (1 at back panel, red, Type-A)
|ROG Exclusive Features||Slow Mode|
SupremeFX Impact III
Impact Power III:
– MicroFine Alloy Chokes
– 10K Black Metallic Capacitors
– IR3553 PowIRStage® MOSFETs
– One-click Overclocking
– Power On
UEFI BIOS features:
– O.C. Profile
– GPU.DIMM Post
– Tweakers’ Paradise
– ROG SSD Secure Erase
– Graphic Card Information Preview
|Special Features||OC Design – ASUS PRO Clock Technology|
– Full BCLK range for extreme overclocking performance
5-Way Optimization by Dual Intelligent Processors 5
– 5-Way Optimization tuning key perfectly consolidates TPU, EPU, DIGI+ Power Control, Fan Xpert 3, and Turbo App
ASUS Wi-Fi GO!
ASUS Exclusive Features:
– AI Suite 3
– Ai Charger+
– USB 3.1 Boost
– Disk Unlocker
– Mobo Connect
– PC Cleaner
– Media Streamer
ASUS EZ DIY:
– ASUS CrashFree BIOS 3
– ASUS EZ Flash 3
– ASUS USB BIOS Flashback
– Push Notice
– ASUS Q-Shield
– ASUS Q-Code
– ASUS Q-LED (CPU, DRAM, VGA, Boot Device LED)
– ASUS Q-Slot
– ASUS Q-DIMM
– ASUS C.P.R.(CPU Parameter Recall)
|Operating System Support||Windows® 10 , 64bit|
Windows® 8.1 , 64bit
Windows® 7 , 32bit/64bit
|Back I/O Ports||1 x HDMI|
1 x LAN (RJ45) port(s)
1 x USB 3.1 (black)Type-C
1 x USB 3.1 (red)Type-A
4 x USB 3.0 (blue)
1 x Optical S/PDIF out
3 x Audio jack(s)
1 x Clear CMOS button(s)
2 x Wi-Fi antenna port(s)
1 x USB BIOS Flashback Button(s)
1 x Q-Code LED
1 x Start Button
1 x Reset Button
|Internal I/O Ports||1 x U.2 port|
1 x USB 3.0 connector(s) support(s) additional 2 USB 3.0 port(s)
4 x SATA 6Gb/s connector(s)
1 x CPU Fan connector(s) (4 -pin)
1 x Chassis Fan connector(s) (4 -pin)
1 x 24-pin EATX Power connector(s)
1 x 8-pin ATX 12V Power connector(s)
1 x Front panel audio connector(s) (AAFP)*2
1 x System panel(s)
1 x ProbeIt Measurement Points
1 x Thermal sensor connector(s)
1 x 5-pin EXT_FAN(Extension Fan) connector
1 x LN2 Mode jumper(s)
1 x SupremeFX Impact II connector(s)
1 x Slow Mode jumper(s)
1 x SupremeFX Impact III connector
1 x M.2 socket pre-installed with a Wi-Fi/Bluetooth module
1 x System panel connector
4 x SATA 6Gb/s cable(s)
1 x CPU installation tool
1 x Supporting DVD
1 x ASUS 2T2R dual band Wi-Fi moving antennas (Wi-Fi 802.11a/b/g/n/ac compliant)
1 x Fan Extension Card (3 x 4-pin fan out)
1 x Fan Extension card screw pack
1 x 12 in 1 ROG Cable Label(s)
ROG Fan Label
1 x 5-pin to 5-pin cable
1 x Panel cable
1 x Thermistor cable(s)
|BIOS||1 x 128 Mb Flash ROM, UEFI AMI BIOS, PnP, DMI3.0, WfM2.0, SM BIOS 3.0, ACPI 5.0, Multi-language BIOS, ASUS EZ Flash 3, CrashFree BIOS 3, F11 EZ Tuning Wizard, F6 Qfan Control, F3 My Favorites, F9 Quick Note, Last Modified log, F12 PrintScreen, F3 Shortcut functions and ASUS DRAM SPD (Serial Presence Detect) memory information.|
|Manageability||WfM2.0, DMI3.0, WOL by PME, PXE|
ROG GameFirst technology
ROG Mem TweakIt
DAEMON Tools Pro Standard
|Form Factor||Mini ITX Form Factor|
6.7 inch x 6.7 inch ( 17 cm x 17 cm )
|Note||*1 This function will work depending on the CPU installed.|
*2 AAFP connector is built-in on the SupremeFX Impact III card
Packaging & Accessories
The Maximus VIII Impact box will look familiar to anyone that has seen a ROG motherboard box before. It’s mostly red with the front sporting the ROG logo and product name, and the back shows a few features and a specifications table.
Since the box is rather small, it also has a flap that when flipped up reveals details on a multitude of other important features of the Maximus VIII Impact including the following: SupremeFX Impact III audio, Impact Power III VRM section, KeyBot II, RAMCache, Overwolf, and some networking details.
The accessories included with the Maximus VIII Impact are fairly typical of high-end ITX boards. We have a User Guide, driver disc, rear I/O cover, four SATA cables, WiFi antenna, front panel extension cable, cable labels, CPU installation tool, temperature sensor, and a unique daughterboard which adds three fan headers.
ASUS Maximus VIII Impact
Let’s start off with a 360° isometric view of the Maximus VIII Impact. If you have never seen an ITX board, the the first thing you’ll notice is the insanely small form factor of 6.7 x 6.7 inches (170 x 170 mm). Next, you’ll notice how much seems to be packed into such a small board. Of course, ASUS sticks to their typical color scheme of black, gray, and red. However, the red is toned down with the board being mostly black/gray with red highlights here and there.
The following is quick overview of some hardware features of the Maximus VIII Impact. We’ll go over these things in more detail later on in the article.
A Closer Look
Now let’s take a closer look at what the Maximus VIII Impact has to offer hardware-wise. Starting in the upper left corner…there’s not a whole lot going on except for a fan header and the header for the daughterboard which adds more fan headers. The 2 x 2 array of pins located below the screw hole are for temperature sensors. You can also see the CMOS battery up against the USB3.0 stack, but other than that, this is basically the fan header section of the board.
There’s not much to the top right corner, so we’ll mention the LGA1151 socket here along with the two DDR4 DIMM slots which support up to 4133 MHz overclocked RAM, 8-pin CPU power connector, and 24-pin motherboard power connector. I personally love how the power connectors are both located on the right edge of the board for easier cable routing and cleaner looking cable management.
In the bottom right corner of the board we have the Z170 Sunrise Point chipset, the PCIe 3.0 x16 slot, four SATAIII ports, front panel header, speaker header, fan header, and USB3.0 header.
On to the bottom left, below the Wi-Fi Go! is a U.2 connector which is an uncommon sight since it’s the newest SSD connector. U.2 (formerly SFF-8639) provides four PCIe 3.0 lanes for transfers up to 3940 MB/s. The downside to this connector is the low adoption for now, and the only SSD option I know of using this standard is the Intel 750 Series. An M.2 connector would have been better for existing compatibility, but ASUS is about top performance when it come to their ROG products and chose to use the U.2 connector for the Maximus VIII Impact.
This corner also has some interesting features for the extreme overclocker. Next to the U.2 connector there’s a removable BIOS chip which allows for easy replacement in case of a bricked BIOS. To the right of the BIOS chip we have two jumpers, one for slow mode and one for LN2 mode. LN2 mode helps avoid cold-boot bugs that can limit overclocking while using sub-zero cooling. Slow mode reduces the CPU frequency which can help prevent instability when the processor has an optimum temperature range at a certain frequency and the temperature is going outside of that range. Reducing the frequency via Slow Mode widens the stable temperature range, so this jumper may need to be switched on and off multiple times (depending on load) while overclocking to keep the CPU temperature in the stable range.
Underneath the SupremeFX Impact III sound card is where the voltage read points are located. This may seem like an odd location for the read points since they cannot be accessed unless the sound card is removed, but it’s really a non-issue. In situations where access to the read points is needed, in-OS sound isn’t needed. The most likely use for the read points is for board testing and extreme overclocking.
On to the rear I/O…to the left of the Impact Control section there is an optical audio port and a HDMI out for using the integrated graphics of the CPU. On the right side of Impact Control there is a stack of four USB 3.0 ports, ASUS 2T2R 802.11AC/Bluetooth 4.1 module, SupremeFX Impact III sound card, RJ45 port powered by an Intel i219-V, and two USB3.1 ports (one Type-A and one Type-C).
The rear I/O may seem kind of barren of connectivity because the Impact Control takes up a lot space. However, that’s a sacrifice that had to made to provide easy access to the following features:
- Q-Code – A POST code display placed on the rear I/O aids in troubleshooting when POST fails.
- Start/Reset Button – Placed at the rear I/O so that the Impact can be used on open test beds.
- BIOS Flashback Button – A low-level, low-risk method of updating UEFI. When the board is in standby state, insert a FAT32 formatted USB flash drive in the correct USB port (location shown on rear I/O cover), with the file renamed to M8I.CAP and hold the button until it starts flashing. Wait until the light stops flashing, then power up the board and let the update procedure complete.
- Clear CMOS Button – Allows clearing the CMOS without having to move onboard jumpers or reach inside a cramped mini-ITX case.
It’s worth mentioning that the RJ45 port is sporting the ASUS LANGuard feature, which provides around double the surge and static electricity tolerance of standard RJ45 ports.
One of the most unique features of the ASUS ITX boards is the VRM section is on a separate PCB to allow more components without taking up space on the motherboard. Of course, a solution like this is only needed for ITX boards competing with top of the line ATX boards in heavy overclocking, which is exactly what the Maximus VIII Impact intends to do.
The Maximus VIII Impact uses custom designed MicroFine Alloy Chokes for high permeability, with half the inductance loss, 75% less hysteresis loss, and higher efficiency than standard chokes which also results in 30% lower operating temperatures. The 10K Black capacitors have five times the lifespan of conventional capacitors and operate at a wider temperature range of -75 °C to 125 °C. The last major component of the VRM is the MOSFETs which are of International Rectifier’s PowIRstage variety. These are all-in-one drivers with integrated high side & low side MOSFETs and are arranged in a 6-phase CPU (Vcore) power delivery circuit.
SupremeFX Impact III Sound Card
Here we have a picture of the SupremeFX without its EMI shield. Listing components from left to right we have the front panel audio header, de-pop relay, clock generator, above the clock generator is the amp, to the right of the clock generator is the DAC, above the DAC is the 2VRMS driver, six capacitors further right, SupremeFX codec, and finally the I/O ports. Also, notice the “white squares” to the left of the I/O ports; those are LEDs that help distinguish which port is which by shining their light through the port hole for external visibility. A blue LED for the LineIn, green LED for LineOut (speakers/headset), and red LED for Mic input.
Here’s some details on the specific hardware used in the SupremeFX and differences between 2015 and 2014 models. This year’s model has an ESS ES9023P DAC, a dedicated clock generator, upgraded Nichicon Capacitors, a RC4580 2VRMS Driver, and a De-pop Relay.
Fan Extension Card
The three fan headers provided via the extension card are a nice addition to an ITX board with limited space. ASUS also added three temperature sensors between the fan headers as well for additional monitoring of air temps around the system.
Diving into the UEFI BIOS, we’ll start off by taking a look at EZ Mode (F7 switches between EZ/Advanced Mode). EZ Mode has everything the novice would need to access in the BIOS: CPU speed/voltage/temp, RAM speed/capacity, XMP switch, fan controls, boot order, and EZ System Tuning. Hitting F7 and switching to Advanced Mode is where all the details can be found. The first tab is My Favorites, and it’s basically a custom tab you create with whatever settings in the BIOS you want to have easy access to. That tab is actually my favorite, just as its name implies…
Q-Fan Control is accessed by hitting the F6 button or by navigating through the Tool tab of the BIOS. Here we have completely open access to independently controlling all fans connected to the Maximus VIII Impact whether they’re connected to one of the two onboard headers or the headers on the Fan Extension Card. On the left, we can choose which header to control, then, at the bottom, choose one of the four fan profiles provided by ASUS or we can select Manual to create our own profile. Not only that, but we can even choose whether to use PWM or DC to control the fans. So, it doesn’t matter if all your fans are PWM or not.
Extreme Tweaker, the third tab, is where the overclocker will spend most of his time. This is where all the expected overclocking settings are located, such as BCLK frequency, CPU Core Ratio, RAM frequency, and all the voltages needed when overclocking. The RAM timings are located in their own sub-section which includes RAM timing profiles provided by ASUS for specific DRAM ICs.
The Advanced tab has a lot of different settings to go through, but not many that are used often. The CPU Configuration section allows you to enable/disable CPU cores, Hyper-Threading, EIST, and C1E. The PCH Storage has all of the settings related to the SATA ports like disabling ports, disabling the whole controller, changing SATA mode between ACHI and RAID, etc. A few settings in the Onboard Devices Configuration tab could be useful such as enabling/disabling Bluetooth or Wi-Fi.
I grouped Main and the last four tabs together since there isn’t much to them. The Monitor tab is kind of self-explanatory, but it’s where the motherboard monitors fan speeds, temperatures, and voltages. The Boot tab is useful when needing to edit the boot order or boot from a specific devices that normally isn’t booted from. The Tool tab has the ASUS EZ Flash 3 utility for upgrading the BIOS, Secure Erase for wiping storage drives, and overclocking profiles.
AISuiteIII is the major piece of software bundled with ASUS motherboards. Once it’s opened you’re greeted with a general window that shows the different sections available: TPU, Fan Xpert, DIGI+, Turbo App, and EPU. The sections most useful to overclockers are TPU and DIGI+ Power Control. TPU is where we’re given the option to set the frequencies and voltages of the CPU, and that section is complemented by the DIGI+ section where we can change how the power delivery functions with settings like load line calibration. Another section that could be useful to quite a few people is Fan Xpert to control how the system fans run based on individual profiles.
Across the bottom the different modules can be expanded by clicking the red triangle arrows to reveal monitoring for that specific module. The EPU section allows you to configure how each of three power states behaves.
Mem TweakIt was designed to allow the ability to change RAM settings in OS for quick testing. However, with Skylake and other recent platforms, Mem TweakIt is basically just an insanely detailed CPU-Z for your RAM since the settings cannot be adjusted within the OS.
RAMDisk and RAMCache allow the user to set extra RAM aside for use as its own separate disk or as cache to an existing HDD/SSD installed in the system.
Sonic Studio II is the audio tuning suite with a virtual surround sound option and controls including Equalizer, Reverb, Bass Boost, Voice Clarity, and Smart EQ. Perfect Voice has the ability to improve both your own and incoming voice communication quality by reducing distortion and noise artifacts.
Sonic Radar II is a unique piece of gaming audio software designed with first-person shooters in mind that gives you is positional audio for allies, enemies, and sound effects.
KeyBot II let’s you set up hotkeys and macro profiles for different games that will automatically switch between profiles based on the current program.
A couple of things to mention about my test setup… The CPU cooling is quite overkill, but it should rule out temperature limiting my overclock. The 8800 GTX is just something I had to throw in there to make sure the IGP of the 6700K didn’t use any system RAM during testing.
|CPU||Intel i7 6770K @ 4.2 GHz, 1.3 V|
|CPU Cooler||EK Supreme HF Full Nickel|
Scythe Gentle Typhoon AP-15
|Motherboard||ASUS Maximus VIII Impact|
|RAM||Patriot Viper 4 16 GB DDR4-3000 15-15-15-35, 1.35 V|
|Graphics Card||NVIDIA GeForce 8800 GTX|
|Hard Drive||Western Digital Black 640 GB|
|Power Supply||SeaSonic Platinum-1000|
|Operating System||Windows 7 Pro x64 SP1|
|Benchmarks||AIDA64 Engineer (v5.50.3600)|
x264 HD Benchmark (v5.0.1)
POV Ray (v3.7)
Intel XTU (v188.8.131.52)
|Fluke 115 Digital Multimeter|
Load Line Calibration
When overclocking for 24/7 use, you want to be able to set a Vcore and know it will stay put regardless of CPU load to guarantee stability. If the voltage drops while loaded, then you may need to increase the set/idle Vcore by that difference to make sure it doesn’t drop below the Vcore you want. This means the idle Vcore would be higher than needed and load Vcore would be exactly what’s needed. Using that method causes the system to use more power when in an idle or low-load state, which is typical state of most users’ PCs. That’s where Load Line Calibration comes into play by helping stabilize the fluctuations in voltage as CPU load changes.
There are eight different levels of LLC available on the Maximus VIII Impact, which may seem like overkill when most motherboards only have a few different settings for LLC or even none. To check the different levels, I set the Vcore to 1.300 V in the BIOS, then booted into the OS. Once loaded, I used my Fluke 115 DMM to check idle Vcore on the onboard voltage read points, then I started running LinX to check the lowest Vcore while the CPU was loaded. Out of the eight levels, level 6 was the most consistent between idle and load Vcore, but also had small, split-second spikes to a higher Vcore when load changes between idle and load states. So, I’ll definitely be using level 6 when overclocking the Maximus VIII Impact.
Overclocking the CPU with the Maximus VIII Impact was easy. I was able to reach 4.8 GHz by using just the CPU core ratio and Vcore, so getting a good 24/7 overclock should be easy even for a beginner. The Vcore required for 4.8 GHz turned out to be 1.38 V, which doesn’t seem to bad to me (although, I’m new to the platform). Temperatures reached 84 °C on the hottest core, even with a custom water loop consisting of a 120 x 480 mm radiator. Skylake definitely produces higher temperatures than Haswell, which is expected with Skylake being a higher wattage over a smaller area.
I ran the benchmarks at both 4.2 GHz and 4.8 GHz on the i7 6700K, so a ~14% difference in clock speed. This resulted in a 12.65% increase in scores on average (9.1-14.4% range), excluding MaxxMEM and AIDA. MaxxMEM and AIDA did show a small increase in performance, just not much since those are RAM benchmarks and aren’t affected by CPU speed very much.
The aesthetics of the Maximus VIII Impact are in line with the rest of their ROG products, past and present, with its black and red theme. I personally like their current iteration of toning down the red and using it as a highlight to the black and gray on the heatsinks and sound card.
The dedicated power section PCB and SupremeFX sound card allows ASUS to save space on the board without compromising on quality. Having the POST code display, power/reset buttons, clear CMOS, and BIOS flashback accessible from the rear I/O is a boon to those who like to tinker without removing the board from its case.
The UEFI BIOS is one of the best around with countless features and settings for anyone regardless of experience, with my favorite being the customizable My Favorites tab where I can have easy access to everything I need while overclocking. The in-OS software, AISuiteIII, is great for quick overclock testing, fan control, and monitoring.
The Maximus VIII Impact makes overclocking easy for the novice while offering features for an experienced sub-zero clocker. Getting the i7 6700K up to 4.8 GHz didn’t take more than a voltage bump to 1.38 V and a multiplier change to 48. However, with its robust power section, LN2 mode, and slow mode this ITX board has what’s needed to compete with the big ATX boards in extreme overclocking as well.
The Maximus VIII Impact comes in at $248.99 on Newegg.com which is the most expensive Z170 ITX board available. In my opinion, the price is more than made up for with the physical design and engineering, multitude of software applications, and add-ons such as the fan extension card. So, for the average consumer, the Maximus VIII Impact would be overboard when there are other cheaper ITX options available. But, if you are in the market for the best ITX board available and planning to overclock moderately to heavily with the possibility of sub-zero cooling, then the look no further than the Maximus VIII Impact.
– Matt T. Green (MattNo5ss)