Tom's Hardware Verdict
Though it technically supports Intel’s Core i9-9900K, frequent throttling ruined enough of our performance measurements that we can only recommend ASRock’s Z390 Extreme4 to users of lesser processors.
Pros
- +
Supports x16/x0 to x8/x8 conversion for SLI
- +
Unsurpassed overclocked memory performance
- +
Inexpensive
- +
Default thermal limits protect undersized voltage regulator
Cons
- -
Consumes far too much full-load power
- -
Frequent voltage-regulator thermal throttling with Core i9-9900K
- -
Gen2-style USB front-panel header runs at Gen1 spec.
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Features and Layout
ASRock's Z390 Extreme4 officially supports Intel’s latest high-end mainstream processor, the Core i9-9900K. But that doesn’t mean it should be used with that CPU, as we'll see later in our testing.
Priced around $160 US (and also around £160 in UK), the Z390 Extreme4's target buyers are probably looking at something closer to the Core i5-9600K. And given the board’s similarities to its Z370 predecessor, we think it will probably support the mid-level CPU quite handily. But it’s still competing against other boards that can properly support the Core i9-9900K’s high power requirement, its failure to keep up with those competing models puts a significant ding in its approval rating.
Specifications
| Socket | LGA 1151 |
| Chipset | Intel Z390 |
| Form Factor | ATX |
| Voltage Regulator | 12 Phases |
| Video Ports | DisplayPort 1.2, HDMI 1.4, VGA |
| USB Ports | 10 Gbps: (1) Type-C, (1) Type A5Gb/s: (4) Type A |
| Network Jacks | (1) Gigabit Ethernet |
| Audio Jacks | (5) Analog, (1) Digital Out |
| Legacy Ports/Jacks | (1) PS/2 |
| Other Ports/Jack | Antenna Bracket |
| PCIe x16 | (3) v3.0 (x16/x0/x4, x8/x8/x4) |
| PCIe x8 | ✗ |
| PCIe x4 | ✗ |
| PCIe x1 | (3) v3.0 |
| CrossFire/SLI | 3x / 2x |
| DIMM slots | (4) DDR4 |
| M.2 slots | (2) PCIe 3.0 x4* / SATA*, (1) M.2 Key-E (*Consumes SATA Ports 0/1, 4/5) |
| U.2 Ports | ✗ |
| SATA Ports | (8) 6Gb/s (Ports 0/1, 4/5 shared w/M.2) |
| USB Headers | (1) 5Gb/s Type-C, (2) v3.0, (2) v2.0 |
| Fan Headers | (5) 4-Pin |
| Legacy Interfaces | Serial COM Port, System (beep-code) Speaker |
| Other Interfaces | FP-Audio, D-LED, (2) RGB-LED, Thunderbolt AIC, TPM |
| Diagnostics Panel | ✗ |
| Internal Button/Switch | ✗ / ✗ |
| SATA Controllers | Integrated (0/1/5/10), ASM1061 PCIe |
| Ethernet Controllers | WGI219V PHY |
| Wi-Fi / Bluetooth | ✗ |
| USB Controllers | ASM1074 Hub |
| HD Audio Codec | ALC1220 |
| DDL/DTS Connect | DTS Connect |
| Warranty | 3 Years |
Features
Sitting at the middle of ASRock's consumer motherboard line, the Extreme4 has long offered users a cheaper way to achieve a mild overclock from high-end processors. That same concept has applied whether we were talking about the 8700K, the 7900X, or even some of its AMD offerings. Prices always reflected a big difference in power requirements between Intel’s big and little processors, but enthusiasts could count on the Extreme4 series to deliver value that was at least competitive to other boards that used the same socket.
But Intel’s decision to wedge the eight-core, sixteen-thread Core i9-9900K into the smaller “mainstream” socket left ASRock in a bind: Did Intel really expect value-seeking enthusiasts to pay an extra 25 percent for higher-capacity voltage regulation? ASRock doesn't seem to think so.
The Z390 Extreme4’s larger heatsinks are intended to deal with the higher continuous power draw of the newer Core i9 CPU, and the Z370-version’s USB 3.1 Gen2 controller disappears in favor of the Z390’s integrated Gen2 support, but we lose an internal USB 2.0 header. Smaller changes such as the addition of addressable LED and a second RGB connector might be more pertinent to the current market.
Two dual-port USB 2.0 headers remain, as do the Z370-version’s original two USB 3.0 and single Gen2 front-panel header--and that Gen2 header still runs at Gen1 speed (5Gb/s), just like on the Z370 model. The two metal-reinforced PCIe slots run at either x16/x0 or x8/x8 mode, depending on whether a card occupies the second slot. The bottom PCIe slot runs at x4 mode off the chipset’s integrated hub, and the three PCIe x1 slots are ocne again open-ended to support longer cards. The Z390 Extreme4 adds a decorative aluminum “heat spreader” cover over its lower M.2 storage slot, and repositions its Key-E slot (typically used for Wi-Fi/Bluetooth cards) to the center of the board while adding the CNVi mode that’s exclusive to Intel’s newer chipsets.
The Z390 Extreme4 loses the Z370 version’s DVI-D output, but gains DisplayPort, all while maintaining the legacy VGA port. The two-hole Wi-Fi antenna bracket is remains, but the motherboard’s installation kit doesn't include the needed cables to run between the bracket and any Wi-Fi card that a builder might otherwise be tempted to place at the mid-board Key-E slot.
The USB port configuration matches that of the old board, apart from its two Gen2 ports being connected to the Z390’s newly-integrated controller. The PS/2 keyboard/mouse port is still there, Gigabit Ethernet still comes from Intel’s i219 PHY, and the ALC1220 audio codec is still bolstered with DTS Connect to output live multichannel streams through the board’s digital optical port (to a DTS receiver, of course).
Z390 Extreme4 buyers get the good overall layout of the previous Z370 model, with all of the stiff perpendicularly-oriented cable headers paced above the top x16 slot to avoid card conflict. There’s still the possibility of a fan connector standing too tall beneath the lowest slot to allow a graphics card to be shoved in all the way, but a four-lane slot that shares those four lanes of bandwidth with all M.2 slots and SATA ports isn’t exactly optimal for graphics card placement anyway. ASRock adds a four-pin ATX12V connector to the 8-pin EPS12V, but we’re more concerned with the board’s capability than that of our cables (though your cables might be less robust than ours).
Z390 Extreme4 buyers get a driver disc, printed documentation, an I/O shield, four SATA cables, a legacy high-bandwidth SLI bridge, and a case badge to go with their board.
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