Asus’ ROG Maximus XII Extreme, built on the Intel Z490 chipset, is the company’s flagship motherboard for the Intel LGA1200 socket and 10th Generation “Comet Lake-S” CPUs like the Core i9-10900K. It should come as no surprise, then, that this oversize Extended ATX (E-ATX) board is simply spilling over with premium features, including AI-assisted overclocking and a fancy OLED display that broadcasts system status (and, if you like, custom animations). Designed for advanced users who will tweak and liquid-cool their components with abandon, this board also supports high-speed memory profiles and other tweakables that put it way beyond the focus of casual PC builders. The “Extreme” in the name isn’t kidding in other ways, too: This board is proudly, boldly pricey at $750. But if you’re looking for one of the best Z490 boards of all, the Maximus XII Extreme is your jacked-up luxury ride; it’s our pick of the moment for high-end Intel motherboards.
The Board Design
The Maximus XII Extreme is coated mostly in black, with a prominent white strip that runs diagonally from the rear I/O panel to the chipset heatsink. This line stands out more after you power up the board; doing so activates a line of RGB LEDs that runs parallel to it. You’ll also spot another string of RGB LEDs tracing down the right side of the board.
Also, a few areas have polished-metal plating with a mirror-like shine. The middle one of these plates is actually a 2-inch OLED panel that Asus calls a LiveDash display. I’ve seen panels like this on a few high-end motherboards before (MSI has put them on some of its Godlike-branded ones), and it’s an awesome feature from both a practical and a bling point of view. By default, this panel will play a few preset animations, and it displays information about your system during the boot process.
This is helpful, but you can also set the panel to display a custom image or a custom animation loop. Customizing the OLED panel gives the system a feeling of projecting something unique to you, as opposed to the same board as everyone else, which makes it a neat option for tech enthusiasts building a PC into a high-visibility, glass-sided chassis with lots of transparency.
Okay, enough OLED-ding around—on to the more important board components. Asus designed the ROG Maximus XII Extreme with a set of 16 Infineon TDA21490 power stages, each of which is able to handle up to 90 amps of current. These parts are also well cooled by a set of three large black heatsinks and a metal heatpipe that runs between them and on down to the chipset heatsink.
You won’t spot here any integrated fans to help keep the VRMs cool, though, which is a bit of a bummer. Lately, I’ve seen more than a few competing boards that have dedicated, albeit small, fans built in to actively cool the power circuitry. Asus makes up for this somewhat by including a small fan that you can attach to one of the VRM heatsinks, and this probably helps some. But it would have been better to have this attached to one of the heatsinks straight from the factory.
The ROG Maximus XII Extreme has a metal backplate over the back of the board that is also supposed to help with cooling. I can’t quantify how effective it is at that, but it definitely makes the board feel sturdy and durable. You won’t have to worry about PCB flex when struggling with ornery, stiff cables like the main 24-pin power connector.
The lower half of the motherboard is covered by one large heat spreader that makes contact with the chipset heatsink and spans the board’s two integrated M.2 slots. As this spreader comes off as one large, solid piece (and because it wraps around all of the PCI Express slots), you won’t be able to remove it without first pulling any PCI Express cards you may have installed.
This large heat spreader isn’t difficult to remove, but I personally don’t like the design. I’d prefer to be able to remove the heat spreader in pieces and access the M.2 slots as easily as possible. Due to the limited room on the motherboard, this often isn’t possible (Asus is hardly alone in being guilty of this kind of design), but realistically there isn’t any need for this heat spreader to wrap around the PCIe slots. The added surface area might help some with cooling, but if Asus’ designers had run separate spreaders directly between the two PCI Express x16 slots, or sectioned it into smaller removable pieces, then only a card installed in the primary PCIe x16 slot might get in the way of removing it. So plan what M.2 devices, if any, you want underneath of time, and install ’em first!
Worth noting while on the M.2 topic: On the board itself you get two M.2 Type-2280 slots, both supporting PCI Express 3.0 x4 drives, with one of those slots also supporting SATA M.2 drives. You can add two additional drives via an Asus-exclusive method, the DIMM.2 module, that I’ll get into in a moment.
Over in the upper right hand corner, you can find a few onboard extras, including an 88-style LED panel for debugging, a power button, and what Asus calls a FlexKey. By default, the last is set to function as a reset switch, but it can be configured to do other things, such as enter the BIOS or change between LED illumination patterns. Also, sandwiched between the debug LED panel and the power button are three switches. Two of these are listed as “RSVD” switches meant to be used solely by Asus technicians and that shouldn’t be touched, but the third one enables the system to boot in a slowed-down mode, which may be helpful if you are doing extreme overclocking.
The four DIMM slots are in the same region, and capable of supporting up to 128GB of memory via four 32GB modules. The board does, of course, support standard memory speeds up to 3,600MHz, but Asus’ OptiMem III technology on the board (which involves, according to the company, more resilient traces) can accept higher frequency and lower latency settings, with the expectations of memory overclock support up to 4,800MHz.
A Brief Look at the Networking and Audio
As Asus’ flagship motherboard on Intel’s mainstream desktop platform, it should come as no surprise that the Maximus XII Extreme comes equipped with top-notch networking hardware.
Look closely, and onboard you’ll spot an integrated Marvell AQtion AQC107 10Gbps Ethernet controller a slower (yet still quite powerful) Intel I225-V 2.5Gbps NIC. These two chips give the board the ability to access the Net extraordinarily fast over a properly provisioned wired connection.
If you prefer to use Wi-Fi, the board also has an Intel Wi-Fi 6 controller (the usual AX201). Though it can’t match the speed of the wired networking hardware, with a maximum data rate of 2.4Gbps, the AX201 is certainly no slouch. You’ll just want to have a Wi-Fi 6-compatible wireless modem to leverage it.
In an interesting move, Asus opted to use separate audio controllers for the front and rear audio jacks on this board. The rear audio jacks connect to a Realtek ALC S1220 audio codec that’s rated for a 120dB signal-to-noise (SNR) ratio. This is a rather common audio chip that we see on virtually every high-end board and most midrange boards nowadays. But that’s fine—it works well; why change what isn’t broken?
The audio jacks on the front I/O panel don’t use the Realtek chip but instead connect to an ESS ES9023 codec. Audio going to the front I/O panel is also pumped through an RC4580 OP-AMP, which is ostensibly better for headphone listening. I find the use of this secondary audio codec a quirky decision on Asus’ part. The ESS ES9023 appears on paper to be a high-quality component, but its SNR is lower than that of the Realtek ALC S1220.
In the real world, SNR is essentially a measure of how much static you’ll be able to hear in the background relative to the sound you’re actually to hear. An SNR of 120dB, for example, would mean that just 1dB of noise is generated for an audio sample with the volume cranked up to the point that it’s 120dB loud. Ultimately, this means that the noise generated by the chip is exceedingly small.
The ESS ES9023 is rated for an SNR of 113dB, which is also relatively high, but if you already have a better solution onboard, why add a second, slightly less capable sound controller? I don’t know, but Asus did. Realistically, the difference between these two won’t amount to much (true audiophiles will use an offboard audio solution or sound card, anyway), but it is a curiosity.
Evaluating the Rear I/O Panel
The rear I/O panel of the Maximus XII Extreme is one place, exactly as it should be on a top-shelf board like this one.
You get a whole army of USB ports, including six USB 3.2 Gen 1 Type-A ports, two USB 3.2 Gen 2 Type-A ports, and two legacy USB 2.0 ports. Also here: two USB Type-C ports, one of which is a 10Gbps USB 3.2 Gen 2, and the other a faster USB 3.2 Gen 2×2 with support for up to 20Gbps of bandwidth. (We’ve just started seeing the first external SSDs that can actually leverage these 20Gbps 2×2 ports, like the Seagate FireCuda Gaming SSD, but they are uncommon.)
You also get two RJ-45 jacks and two wireless-antenna hookups on this back panel for the aforementioned networking hardware. For audio connections, look for a S/PDIF jack here, as well as the usual five 3.5mm audio jacks. Asus tried to jazz these up a bit by adding color-coded lights the 3.5mm jacks. You won’t be able to see these if you actually have something plugged in, or if your PC is wedged into a corner or a desk niche, but the glow is a neat little extra that also has the added benefit of making it easier to plug in audio cables in the dark.
One thing to note: You won’t find any video-out ports on the rear I/O panel, so don’t plan on relying on Intel’s UHD Graphics from the CPU. You’ll need a video card from moment one. Realistically, who’s going to use CPU-integrated graphics on a $750 motherboard? Well, I might, that’s who, but only for troubleshooting, or in the event that my GPU died. Personally, I would have liked to have seen a break-glass-in-case-of-emergency item here in the form of an HDMI output, but it’s perfectly understandable why Asus opted to save the space on the I/O plate. In the end, most of the time, you’d appreciate an extra USB port instead.
The last items of note on the rear I/O panel are two buttons that sit at the top of the board. They can be used to clear the BIOS and to flash the BIOS to a new version from a USB key. Nothing revolutionary, and expected on a tip-top board like this, but these kinds of buttons are always extremely useful to have.
Tasty Motherboard Morsels: A Handful of Nifty Extras
Before we get to building this board up in a case, it’s worth going over the extras that Asus bundles in. I mentioned that the board comes with a small fan for cooling the VRM heatsinks earlier, but it also comes with three electrical components, as well as a flash drive, a screwdriver with changeable bits, and an ROG key chain. The flash drive has the board drivers and utilities loaded onto it, and it has a generous 16GB capacity—who couldn’t use an extra flash drive? But the three electrical components I mentioned are far more interesting.
First up is the Fan Extension Card II, which has connections for up to six case fans, three RGB headers, and three thermal sensors. This could come in handy if your PC case doesn’t have an integrated fan controller. You can see it above at right. With the screw holes in the board, you can mount it in a 2.5-inch drive bay.
Next is one of Asus’ ROG DIMM.2 modules. This vertical-mount module uses a custom-made slot on the motherboard (parallel to the bank of memory DIMM slots) and can hold two additional PCI Express 3.0 M.2 drives. It’s also a lot easier to just grab this card and add an M.2 SSD to it than to pull out all of your PCI Express cards to get at the surface-mounted M.2 slots integrated into the board. It supports up to Type-22110 M.2 SSDs, which is to say, the rare longer SSDs than the much more common 80mm ones supported on the three PCB-flush slots.
The last component is a PCI Express x1 ThunderboltEX 3-TR card. This device has two Thunderbolt 3/USB Type-C ports, as well as two mini DisplayPort-in ports…
It’s also worth mentioning here that the Maximus XII Extreme has a Thunderbolt 14-1 header to support this card; just plugging it into a board PCI Express slot isn’t enough alone. It’s a great extra to have if you have any Thunderbolt 3 devices sitting around, and a rare inclusion for a desktop motherboard. (It certainly contributes to the overall package’s pricing.)
The Building Experience
The PCB for the ROG Maximus XII Extreme complies with the Extended-ATX (E-ATX) form factor, which makes it too large for all but the roomiest computer cases. How easy it is to mount inside of a case will vary greatly depending on the case, but after it’s in, things go quite smoothly.
The CPU power connector and fan headers are often tricky to access on many motherboards with VRM heatsinks and other components cluttering the area around them. But I found them refreshingly easy to access on this board. The VRM heatsinks are spaced out enough that they don’t really block access to either. A case-fan header and a water-block header sit directly beside the CPU power connector, and these are tricky to get at, but I don’t consider this a major issue as they aren’t essential for all users, and you get to them if you make a point of plugging things into them first.
You’ll also see a veritable horde of four-pin fan headers all over this board, with five at the top of the board and an additional six at the bottom. This makes the fan controller included with this board somewhat moot, as few cases are able to hold 10 or more case fans, but at least you won’t have to worry about not having enough places to plug them in.
Installing M.2 solid-state drives onto the motherboard is mildly bothersome, as I noted earlier, but only if you try to install an M.2 drive into one of the board-flush slots last or late in the system assembly process. You get eight SATA 3.0 ports on this board for any 2.5- or 3.5-inch drives you may have on hand, all of which are set at a right angle on the right side of the board. Because the board is E-ATX size, you’ll want to be especially cognizant of having enough clearance on that edge of the board to plug in your SATA cables. Cramming this board into an ATX-only chassis might restrict access to those ports.
Other than that, the rest of the building experience is straightforward and in line with what you’d expect from any modern, upscale mainboard.
A Brief Look at the BIOS
The Asus Z490 ROG Maximus XII Extreme employs essentially the same BIOS as most (if not all) of the company’s other modern high-end motherboards. It’s functional, nice-looking, and responsive, but it does have one quirky aspect.
The BIOS on this board has both an EZ Mode menu and an Advanced menu, but upon first entering the BIOS you are taken directly to the Advanced menu. As this is such a high-end motherboard, you could argue that it doesn’t an EZ Mode menu and that experienced users will want to dive straight into the Advanced menu anyway.
But if you are going to include an EZ Mode, that should probably be what the board boots to first. The entire purpose of a BIOS EZ Mode is a quick, at-a-glance menu. That way, inexperienced users can make small changes without being overwhelmed with the many other options in the Advanced menu. It also helps advanced users that just need to make quick changes (such as enabling a memory profile or changing the boot order).
Plus, the EZ Mode menu here is fairly useful. You can enable memory profiles, adjust the boot order, and override the boot order or boot straight to a device that you select. It also has controls for Asus’ built-in auto overclocking tools, and lets you adjust how the fans spool up at various temperatures.
If you want to do more than that, then you will need to dive into the Advanced menu. A special feature here is the favorites tab, which will allow you to create a custom BIOS menu filled with your most frequently accessed options.
The overclocking tab on this board is labelled as Extreme Tweaker, which I suppose is a more extreme variant of the Tweaker tab found on most other Asus boards. It does have a substantial list of options for overclocking the system. Most basic controls, like the CPU core multiplier, can be accessed directly from here, but if you want to fine-tune your overclock, you can also dive into the Tweaker’s Paradise subsection, which has lots of even finer controls to explore.
The Board Drivers and Software
Installing drivers for the Z490 ROG Maximus XII Extreme took just a few minutes after booting to Windows. Best of all, they all installed without issue even before updating Windows 10. This is important, but especially for the networking drivers, so that you can get online right away to get those updates in the first place. (None of the classic, familiar fumbling with Ethernet drivers on a USB key to get online.)
Asus doesn’t go wholly overboard (pun intended) in terms of software utilities with this model, though there’s plenty; you can use your discretion in what to install. The main dish: You get the company’s standard Armoury Crate application for controlling RGB LEDs and checking for driver updates, plus a copy of Daemon Tools Lite. This software is technically free, but the free version hits you with ads, whereas this is the ad-free paid version. It also has some useful features that enable it to virtually mount disc images and rip images from physical discs to make backup copies.
Beyond that, Asus offers compatible software for memory tweaking (Mem Tweakit), RAM cache, audio EQ, AI-assisted overclocking (if you don’t want to go full-manual), and much more. You also get an ROG-branded version of the seminal CPU-Z for core component monitoring.
A Cadillac Z490, With All the Options
Now that the board is up and running and everything is working perfectly, the last thing to discuss is its price and place in the market. As Asus’ Intel LGA1200 flagship, it’s naturally one of the most expensive motherboards on the market, with an MSRP of $750. You can realistically build entire systems for the price of this board alone, but no $750 system’s board is going to match this one in terms of its premium build quality, tweakability, and features.
Asus have done a few things to reduce the price a bit. The fan expansion card in particular feels like an unnecessary extra, and, realistically, the Thunderbolt 3 card could have been an opt-in. Not that the Thunderbolt 3 card isn’t useful, but shoppers that really need one could just buy one separately. The DIMM.2 accessory is a useful one, and specific to a certain subset of Asus boards, but the other items do boost the price with extras that not everyone is going to want. (Especially the fan-controller gizmo, when the board already has almost a dozen four-pin headers to work with.)
None of this is to say that the Maximus XII Extreme is extravagantly priced against the competition. The MSRP lines up exactly with Asrock and MSI’s flagship boards (assuming you ignore Asrock’s truly bonkers Z490 Aqua), and it undercuts Gigabyte’s by $50. But none of those boards comes with a discrete fan controller or a Thunderbolt 3 card, and only MSI’s includes an M.2 card of sorts (in MSI’s case, a PCI Express carrier card). On the one hand, that means that the Maximus XII Extreme is the flagship with the most extra goodies, but equally appealing would be a flagship that undercuts all the others on price. This is not that.
Overall, if you’re looking to buy one of the best Z490 motherboards on the market for tweaking and price is secondary, or you need the Thunderbolt 3 connectivity, the Asus ROG Maximus XII Extreme will not disappoint. Just make sure you’ll use all or most of the extra hardware in the box, and need all that headroom for memory and overclock, or you’re paying for way more board than you need.
