
The Bottom Line
Introduction, Specifications, and Pricing

ASRock's X99 Mini-ITX was one of a kind, and with the advent of Intel's X299 chipset, ASRock once again breaks the monotony of full-sized ATX motherboards and shrinks the HEDT X299 platform for small form factor (SFFPC) builds. The X299E-ITX/ac has many advantages over its predecessor.
For starters, you get three M.2 slots for drives, quad channel memory (albeit SO-DIMMs), a nice VRM, and even a custom water block you can buy separately. In fact, after working with the motherboard, I highly recommend buying the Bitspower full cover block if you plan on heavy overclocking, as it also cools down the VRMs.
Without further hesitation, let's see what the X299E-ITX/AC has to offer.
Specifications

The X299E-ITX/ac offers three Ultra M.2 slots (two from CPU and one from PCH), USB 3.1, Wireless AC 2x2, dual Intel LAN, a single PCI-E x16 slot, and many other standard features such as USB 3.0 and SATA6Gb/s.
Pricing
The X299E-ITX/ac costs $399.99.
Packaging and X299E-ITX/ac Overview
Packaging and Overview


Box and packaging are done well, and just like other ASRock Mini-ITX products. The motherboard is well protected, and the box resembles the color of the motherboard.

The accessory package includes four SATA6Gb/s cables, three M.2 screws, IO shield, WIFI antenna, ASRock case badge, driver DVD, and manuals.


ASRock has three fan headers on the motherboard that are hybrid DC/PWM headers. The header in the top left corner doubles as a water pump header, so it should run full speed by default. The motherboard has two daughterboards that contain one of the M.2 slots, all SATA ports, a USB 3.0 internal header, and a USB 2.0 internal header. The daughterboard with the M.2 slot also has both Intel NICs and a USB 3.0 hub on it.
Since the Mini-ITX platform is so compact, and the socket is so large, there is almost no getting around adding extra PCB to take on the extra components. The motherboard features quad channel memory support, but you are going to need SO-DIMMs. The back of the motherboard is where you will find two more M.2 slots as well as a lot of circuitry.

The IO shield offers four USB 3.0 ports, USB 3.1 type-A, USB 3.1 type-C, a clear CMOS/Power button, WIFI antenna outputs, as well as gold plated 7.1 audio jacks with S/PDIF out.


The PCI-E lane allotment is really easy to understand; the motherboard offers a single x16 slot that can be split all the way down to x8/x8 or x4/x4/x4/x4 with a riser card. The SO-DIMMs are vertical and offer overclocking support. The M.2 slot on the top of the motherboard is connected to the PCH and offers x4 PCI-E 3.0 or SATA connections. It sits in a modified SO-DIMM slot.


The two M.2 slots on the rear of the motherboard are both x4 PCI-E 3.0 and are directly connected to the CPU. They can only RAID with VROC technology, but that also means you can RAID 0 all three M.2 slots on the motherboard and not be bottlenecked by the PCH to CPU DMI bus.


We find six SATA6Gb/s ports, a USB 3.0 header, and a USB 2.0 header on the daughterboard above the CPU VRM heat sink. A VROC header is located at the top left corner of the motherboard, and a TPM module header is located right behind the WIFI card.


A front panel HD audio header is located above the PCH heat sink. A small switch located to the right of the PCH heat sink allows you to choose what the button of the IO panel does. You can have the button clear CMOS or act as a power button (clear CMOS is default). An RGB LED header sits above the 8-pin power connector. In between the CPU power connector and RGB header are your system headers.


The VRM heat sink screws into the "front" daughterboard, and you need to remove it if you are going to install the Bitspower waterblock. I installed the Bitspower waterblock, and I highly recommend buying it if you are going to overclock HCC CPUs.

The heat sinks on the motherboard cover the VRMs and the PCH. The VRM heat sink isn't that large, so I would try and ensure there is adequate airflow over it.
ASRock X299E-ITX/ac Circuit Analysis
Circuit Analysis

The X299E-ITX/ac is the most unique X299 motherboard I have reviewed.


The motherboard features a 6+1+1 phase VRM for the CPU input voltage, VCCSA, and VCCIO. I want to mention that the motherboard does not support Kaby Lake-X CPUs, only Skylake-X CPUs. ASRock uses Intersil's new high performance ISL99227F 60A Smart Power Stages with internal current and temperature monitoring. The Intersil ISL69138 is used in 6+1 phase PWM mode, and it is part of Intersil's new set of digital PWMs. ASRock also uses 60A inductors for the CPU VCore phases. The VCCSA uses the same Smart Power Stage as the main power supply rail.


For the VCCIO ASRock still employees another ISL69138, but uses an Intersil ISL6596 driver, and a Sinopower SM7341EH dual N-channel MOSFET. The Sinopower is rated for about 25A. We also see one of these driver + dual N-channel FET combos near each set of two DIMMs.


Each memory VRM uses the same Intersil ISL69138 digital PWM, and it kind of seems like a bit of a waste considering the number of rails not used, but I assume ASRock wanted to maximize features, so the motherboard has more digital PWM technology on board than needed. One of the Sinopower dual N-Channel's is hidden under the PCI-E x16 slot.
ASRock X299E-ITX/ac Circuit Analysis Continued
X299-Aorus Gaming 9 Circuit Analysis Continued


The audio hardware on this motherboard consists of the Realtek ALC1220 codec along with a Texas Instruments NE5532 amplifier on the back of the PCB. Gold series capacitors were also used to improve audio quality as well as physical PCB division.


Woah! ASRock dropped that 1x1 433Mbps wireless-AC card and upgraded to the Intel 2x2 867Mbps 8265NGW. The first NIC is an i211AT.


The second NIC is an i219v PHY that works with the integrated MAC in the PCH. The ASMedia ASM3142 USB 3.1 controller is found on a daughterboard.


The ASMedia ASM1543 is used as the type-C switch and CC logic chip. The ASMedia ASM1074 USB 3.0 hub is used to expand USB 3.0 for the rear IO. The odd part is that ASRock could have routed all USB 3.0 to the PCH, as the PCH has many unused HSIO lanes. I believe that ASRock used the hub instead because it reduces the number of traces from the PCH. Mini-ITX boards such as this could use anywhere from 8-10 PCB layers, and reducing traces is the name of the game.


An ICS 6V41742B is used as an extra clock generator to improve BCLK clocking. The nuvoton NCT6791D is the main super IO used for fan control and major system monitoring, as well as the PS/2 port.


The Nuvoton N76E885AT is used for RGB LED control and functionality. The BIOS is a 128Mbit/16MB ROM. We also find an eFuse near the BIOS ROM.
BIOS and Software
BIOS

ASRock's X299E-ITX/ac's UEFI looks similar to those found on other ASRock X299 motherboards and offers all the settings you need to overclock and configure the system. There is rudimentary RGB LED control. Fan control is very well done in the form of a GUI and manual input menu, but you only have three fan headers.
There are two operating modes; an advanced mode and a beginner mode for those who are more novice. You also get the PCI-E bifurcation setting in the UEFI in case you want to use a riser with a PCI-E splitter.
























Software

Software includes ASRock RGB LED, A-Tuning, Restart to UEFI, and APP Shop just to name a few.
Test System Setup
Steven's Motherboard Test System Specifications
- Motherboard: ASRock X299E-ITX/ac
- CPU: Intel Core i9-7960X
- Cooler: Bitspower Custom Block and AIO Rad/Pump
- Memory: G.Skill Ripjaws 3800MHz 8GBx4 SO-DIMM Kit
- Video Card: NVIDIA GeForce GTX 1080 Ti - Buy from Amazon / Read our review
- Storage - Boot Drive: Corsair LS 240GB
- Storage - M.2 Drive: Samsung 950 Pro 256GB
- Storage - USB Drive: Corsair Voyager GS 64GB - Buy from Amazon / Read our review
- Case: Corsair Obsidian 900D - Buy from Amazon / Read our review
- Power Supply: Corsair RM1000 - Buy from Amazon / Read our review
- OS: Microsoft Windows 10 - Buy from Amazon
- Monitor: ASRock PA328 ProArt 32" 4K - Buy from Amazon
- Keyboard: Corsair K70 LUX - Buy from Amazon
- Mouse: Corsair M65 PRO RGB - Buy from Amazon / Read our review
- Headset: Corsair VOID RGB Wireless - Buy from Amazon / Read our review
- BIOS: P1.31



The X299E-ITX/ac with the block and with the G.Skill memory make an extremely beautiful system! I really like how the light is diffused in the block. I picked blue coolant, since TweakTown is blue, and it turned out amazing.
Overclocking With G.Skill 3800MHz SO-DIMMs
CPU Overclocking
G.Skill sent over their special new SO-DIMM kit, which is rated for 3800MHz, comes in four sticks, and it works with the board as if they were made for each other. I also highly recommend the full cover monoblock from Bitspower if you are going to overclock an HCC CPU.


We have switched out the 7900X for the 7960X for the new 2nd wave of X299 motherboards, as the 7960X puts a lot more strain on the overclocking capabilities of the motherboard. We set VCCIN of 2.1v with VCore of 1.195v, set LLC to mode 2, XMP to enable, and then we just save and exit. The motherboard overclocks the SO-DIMMs with such ease; it is almost as if the two are made for each other.
We will have a Mini-ITX build and overclocking guide in the next few weeks, just using this motherboard and RAM kit and explaining how to get everything going, so stay tuned for more!
CPU, Memory, and System Benchmarks
CINEBENCH R15

wPrime

AIDA64 FPU

AIDA64 Memory

ScienceMark

HandBrake

SuperPi 32M

3DMark: Fire Strike

3DMark: Cloud Gate

ResidentEvil 6

The ASRock X299E-ITX/ac is a bit current limited at stock with our BIOS version. ASRock has since provided a new BIOS with different settings, but for these tests, I just unlocked the current limit settings in the UEFI to make it more of a fair fight.
ASRock also sent me a BIOS after my initial testing that had options for this. The motherboard allows the 7960X to keep up in the Mini-ITX form factor. It's a solid motherboard all around, but the SO-DIMMs seem as if they make a bit of a difference in memory benchmarks.
System IO Benchmarks
CrystalDiskMark SATA6G:

CrystalDiskMark M.2:

ixChariot Network Throughput:

ASRock's X299E-ITX/ac has excellent IO and networking performance.
Audio RMAA 5.5:
I disable all audio features, set the correct bitrates, and then test the audio with a loopback test.

Sound Judgment by Ear: Excellent, but I am amazed at how clean some of those numbers look even though the motherboard is so busy. There are five ratings for audio: 1. Problems, 2. Okay, 3. Acceptable, 4. Very good, 5. Excellent
VRM and System Thermal Imaging and Power Consumption
System power is measured at the wall with an AC power meter.

Note on Thermal Images: In the temperature section, we use our Seek thermal imaging camera to capture the surface temperatures of major components on the board. I look at the VRM and then all other things that light up the screen. If there is something to worry about, then I will state it. Otherwise, I will just show the hotter running parts of the board for fun. Unless some component is over 80-90C, then there isn't anything to worry about.
All systems will act differently, so I will look for commonalities, such as how far from the VRM the heat spreads through the PCB and the difference in temperature between the front side and backside of the PCB. Keep in mind, the majority of the heat from the VRM goes into the PCB as it is a giant soldered on copper heat sink. A larger difference in temperature between the back and front of the PCB points towards a more effective heat sink.
Thermal Testing at Stock Speeds:
The image on the left is always at idle, and the image on the right is at load. During ALL TESTS, fans above the VRM that cool the CPU cooler's (Corsair H110i) radiator are turned on to high (12v).


Full frontal.


Up-close of the front of the VRM.


The VRM thermal imaging shows off Intersil's new power stages and PWM controller in a great way. These results are with the waterblock on, and they are awesome results.
Up-close of the back of the VRM.
4.4GHz 2.1V VCCIN OCed VRM Thermal Imaging:
Airflow from the radiator that cools the CPU is directed in the direction of the VRMs from the right side of the motherboard to the left, and a dedicated 120mm fan is mounting above the VRM and blows directly at it. We get our results at loop 25 of Intel Burn Test, they are lower than the temperatures you see above (the stock results), as they don't have the fan over them.


The results are good, but this is about the limits of the motherboard's VRM. You need to watercool the system with the monoblock that also cools the VRMs if you are going to try and overclock any Intel HCC (>10C) CPU on this motherboard. Regardless, at 4.4GHz core with 3.8GHz memory, we find that the CPU isn't throttling and that we are getting higher FPS, albeit at a higher VRM temperature.
Overall, yes, the motherboard can overclock very well, but you will want the monoblock.
What's Hot, What's Not & Final Thoughts
Here are key points about the ASRock X299E-ITX/ac.

What's Hot
The Obvious: It's the only X299 motherboard built in the Mini-ITX form factor. It's a beautiful creation, and the fact that it keeps all major platform features is awesome. You still get quad channel memory, albeit you need to use SO-DIMMs. You get three M.2 slots, and you get a nice serving of USB 3.0 and SATA6Gb/s from the PCH. The motherboard rocks in regards to the way ASRock crammed everything in.
Three M.2 slots, VROC, and no DMI bottleneck: The CPU-to-PCH DMI connection is limited to roughly 3.5GB/s, and when we have M.2 drives that can singlehandedly go up to 3.5GB/s, trying to RAID two of them when connected to the PCH will result in a bottleneck. However, ASRock routed the two M.2 slots on the rear of the motherboard to the CPU, while the one on the daughterboard is routed to the PCH, meaning you can use VROC and RAID three Samsung 960 Pros and not be bottlenecked by the DMI connection. I believe this is one of the only X299 motherboards to allow you to do that with built-in M.2 slots.
Can handle HCC CPUs with Waterblock: The full cover waterblock cools down the CPU, but it also cools down the VRM's power stages and inductors. The result is a Mini-ITX X299 motherboard that can easily handle Intel's 16 and 18 core chips and also overclock them. That is impressive. I got my 7960X to 4.4GHz with ease, and the VRM wasn't throttling the CPU.
Overclocking!: The X299E-ITX/ac easily overclocked my G.Skill 3800Mhz SO-DIMM quad channel kit to 3.8GHz, that's intense. All I had to do was enable XMP. With the full cover block, I can overclock HCC CPUs very high as well, and that's just impressive. While the CPU gets 6 phases, those 6 phases are capable of 350W with the monoblock.
Riser Support: PCI-E bifurcation is the act of splitting up a larger PCI-E grouping into smaller ones. The motherboard supports splitting the x16 slot into x8/x8, x8/x4/x4, x4/x4/x8, and even x4/x4/x4/x4 through a BIOS setting.
What's Not
You are going to need VRM airflow: The built-in VRM block is only really effective when you have airflow over it. It would have been nice to see ASRock include some type of fan bracket. If you get the water block, you won't have issues then.
No 16 lane CPUs: The two current Kaby Lake-X CPUs are not supported on this motherboard. ASRock made that decision because it would require more hardware to support both, and I figure they ran out of trace space.
Final Thoughts
ASRock has done a fine job with the X299E-ITX/ac; it might be one of my favorite X299 motherboards. It's just so cool! I love how ASRock figured out how to get all those components and traces on the motherboard. While the rear IO might look like it could handle more ports, the truth is that you can easily run out of PCB trace space and end up with too much noise with too many features. ASRock struck a nice balance of features to space and even went so far as to consolidate connections and build daughterboards. The motherboard's quality is also top-notch, and ASRock gave it a price tag that reflects its quality.
The cooling solution we used isn't cheap either, it's $164.99, and together with the rad/pump combination, the price tag comes to $349.99. With the motherboard, your price tag comes out to $749.99 for the complete cooling solution and the motherboard, which might be a lot, but if you are going to pack in an HCC Intel CPU like the 7980XE and want to go Mini-ITX, it is an excellent solution.
I would add in the high-speed G.Skill SO-DIMM kit in as well, and that is because the motherboard can easily take full advantage of it. It's an excellent motherboard; there is just nothing else like it on the market.