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Editor's Choice

Tom's Hardware Verdict

The Z390 Gaming X is the cheapest way we know of overclock a Core i9-9900K, even if it needs extra cooling to do so. Users with lower-model processors will have even better results.


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    Consistently under $150

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    Fully supports Core i9-9900K

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    Good overclocking


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    Second PCIe x16 slot has only four PCH lanes

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    No front-panel USB3 Gen2

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    Only one USB3 Gen2 header (on the I/O panel)

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    Hot voltage regulator requires a fan near CPU socket

Features and Layout

Z390 is a requirement for overclocking Intel’s latest processors, yet lower-cost models often abuse that credential by throttling back under the hefty power load of Intel’s high-end Core i9-9900K. Of course, there are buyers who would choose a lesser processor to better match those low-cost boards, which is why we recently retested a few under the lighter load of a Core i5. Among those recent Intel boards we tested, Gigabyte’s Z390 SLI stood out as the one inexpensive option that fully supported both high-end and mid-range processors. The Z390 Gaming X ($150 / £154) offers a similar design to the pricier model, for those who don’t need (or want to pay for) SLI.

Gigabyte Z390 Gaming X Specs

SocketLGA 1151
ChipsetIntel Z390
Form FactorATX
Voltage Regulator12 Phases
Video PortsHDMI 1.4
USB Ports10Gbps: (1) Type A5Gb/s: (5) Type A, (2) USB 2.0
Network Jacks(1) Gigabit Ethernet
Audio Jacks(6) Analog
Legacy Ports/Jacks(1) PS/2
Other Ports/Jack
PCIe x16(2) v3.0 ( x16/x4)
PCIe x8
PCIe x4
PCIe x1(4) v3.0
CrossFire/SLI3x / 2x
DIMM slots(4) DDR4
M.2 slots(2) PCIe 3.0 x4 / SATA(SATA M2-1 excl pt 1, any M2-2 pts 4-5)
U.2 Ports
SATA Ports(6) 6Gb/s (SATA 1, 4/5 shared)
USB Headers(1) v3.0, (1) v2.0
Fan Headers(4) 4-Pin
Legacy InterfacesSerial COM Port, System (beep-code) Speaker
Other InterfacesFP-Audio, RGB-LED, TPM, Thunderbolt AIC
Diagnostics Panel
Internal Button/Switch✗ / ✗
SATA ControllersIntegrated (0/1/5/10)
Ethernet ControllersWGI219V PHY
Wi-Fi / Bluetooth
USB Controllers
HD Audio CodecALC892
DDL/DTS Connect✗ / ✗
Warranty3 Years

So similar is the Z390 Gaming X layout to the previously-tested Gaming SLI that we had to do a double-take, at first glance finding nothing more than the center slot missing the pricier-board’s metal cover and the lower slot switched from x16-length to x1. The fact that the middle slot has only four fixed lanes rather than stealing eight from the upper x16 slot could be seen as a benefit to anyone hoping to use a PCIe x4 storage card there, since it leaves the top slot’s sixteen lanes intact. As for the bottom slot, the change from x16-length to x1 is hardly a problem given that the Gaming SLI’s bottom slot had only two lanes.

A closer look at the I/O panel reveals that the legacy PS/2 port and two USB ports have traded position compared to the Z390 Gaming SLI, and that those two ports have magically transformed from USB 3.0 (aka 3.1 Gen1) to USB 2.0. One of the Gaming SLI’s Gen2 ports is also knocked down to Gen1, leaving only one 10Gb/s connection. We’re keen on the retention of two USB 2.0 ports to connect our keyboard and mouse without eating into the chipset’s HSIO resources, but limiting next-generation USB to just a single port is a bit too limiting for our comfort.

In fact, a quick look up the page to the features table shows that the only resource issues that really mattered with the Gaming SLI are still present with the Z390 Gaming X: The lower M.2 interface still disables two SATA ports regardless of whether an NVMe or SATA drive is installed there, and the upper M.2 slot steals a SATA port whenever it’s filled with an M.2 drive that uses the SATA interface.

The Z390 Gaming X still features the same 10+2 phase voltage regulator as its SLI sibling, which remains fed by both ATX12V (4-pin) and EPS12V (8-pin) headers: The extra 4-pin connector allows users to exceed the 42A current limit of eight pins (four power, four ground) when overclocking.

Other than changes to its x16-length slots, the Z390 Gaming X retains the same lower section as the Gaming SLI. That means the bottom edge includes front-panel audio, S/PDIF breakout cable, legacy serial (COM) port, RGB, TPM, USB 2.0, one (of four) 4-pin fan, Intel-style front-panel LED/button, and PC Speaker headers along the bottom edge.  One key difference is that RGB is not extended to the I/O panel’s decorative internal cover, though an unmasked stripe that follows the audio-to-I/O panel pathway is still lit in red.

The codec itself is also downgraded from the SLI version’s Realtek ALC1220 to its older ALC892.

Gigabyte’s Z390 Gaming X includes a manual, software installation guide, driver and application disc, two SATA cables and M.2 drive screws. Any other connection needs must be filled with the buyer’s own parts, though many of the board’s headers are already addressed by case cables.

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Thomas Soderstrom is a Senior Staff Editor at Tom's Hardware US. He tests and reviews cases, cooling, memory and motherboards.