Four Z87 Express Motherboards For Three- And Four-Way SLI

Making Z87 Express Three-Way SLI-Capable

We've seen incremental updates to Intel's processor architectures yield small performance benefits in games for the past several generations. However, a great many enthusiasts dislike some of the platform restrictions Intel put in place. For instance, CPUs built around the LGA 1156, 1155, and 1150 interfaces have integrated PCI Express controllers limited to 16 lanes of connectivity. Of course, that's a great way to help minimize latency. But Nvidia's official stance is that those available lanes support a maximum of two GeForce graphics cards. A third would force you to split into x8, x4, and x4 links. So what's a fan of three-way SLI supposed to do?

Stepping up to LGA 2011 gives you access to 40 lanes of third-gen PCIe, but you also have to take an architectural step backwards. Up until Intel launched its Ivy Bridge-E-based chips, you actually had to take two steps back. And beyond higher-priced components, you're talking about using more power and generating more heat, too.

But there's a solution, which isn't particularly new. Used to enable AMD's and Nvidia's fastest dual-GPU graphics cards, PLX Technology's ExpressLane PEX8747 48-lane PCIe 3.0 switch acts a lot like a repeater hub, broadcasting the same data to multiple devices, turning 16 lanes on one end of the switch into 32 lanes on the other, without dividing bandwidth (since CrossFire and SLI require all GPUs to receive identical data).

The usual marketing caveats apply, beginning with PLX calling this a 48-lane switch when, again, it takes 16 lanes on one end and facilitates 32 on the other. Moreover, three- and four-card configurations do cause bandwidth division, cutting dual 16-lane links into eight-lane interfaces. And finally, there’s the slight latency penalty of adding another component, though that seems minor considering both graphics vendors drop the switch onto their GeForce GTX 690 and Radeon HD 7990 without negative consequence.

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LGA 1150 ATX Motherboard Features
Row 0 - Cell 0 ASRock Z87 Extreme9/acAsus Z87-WSGigabyte Z87X-UD7 THMSI Z87 XPower
PCB Revision1.
ChipsetIntel Z87 ExpressIntel Z87 ExpressIntel Z87 ExpressIntel Z87 Express
Voltage Regulator12 PhasesEight Phases16 Phases32 Phases
BIOSP2.00 (11/27/2013)1504 (10/04/2013)F2 (11/08/2013)1.4 (11/27/2013)
100.0 MHz BCLK100.00 (+0.00%)99.94 (-0.06%)99.77 (-0.23%)100.01 (+0.01%)
I/O Panel Connectors
P/S 21111
USB 3.06468
USB 2.024None2
CLR_CMOS Button1NoneNone1
Digital Audio OutOpticalOpticalOpticalOptical
Digital Audio InNoneNoneNoneNone
Analog Audio5656
Video OutHDMI, Dual ThunderboltMini DisplayPort 1.2, HDMI, Full DisplayPortDual HDMI, Dual Thunderbolt (Three displays)Dual HDMI, DisplayPort
Other DeviceseSATA, DisplayPort In (for pass-through)Dual eSATA, USB BIOS FlashbackNoneWi-Fi/Bluetooth Module
Internal Interfaces
PCIe 3.0 x164 (x16/x0/x16/x0 or x8/x8/x8/x8)4 (x16/x0/x16/x0 or x8/x8/x8/x8)4 (x16/x0/x16/x0 or x8/x8/x8/x8)4 (x16/x0/x16/x0 or x8/x8/x8/x8)
PCIe 2.0 x16NoneNoneNoneNone
PCIe 2.0 x11-standard, 1-Mini (filled)222
USB 3.02 (4-ports)1 (2-ports)2 (4-ports)2 (4-ports)
USB 2.03 (6-ports)2 (4-ports)2 (4-ports)2 (4-ports)
SATA 6.0 Gb/s10 (shared with eSATA)10 (shared with mSATA)1010 (shared with mSATA)
4-Pin Fan2677
3-Pin Fan4None2None
S/PDIF I/ONoneOutput OnlyBothNone
Internal ButtonsPower, ResetMemOK, CLR_CMOS, DirectKey, Power, ResetRatio +/-, BCLK +/-, CLK increments, OC Turbo, OC Tag, OC IGN, Power, Reset, CLR_CMOSRatio +/-, BCLK +/-, Discharge, OC Genie, Go2BIOS, Power, Reset, CLR_CMOS
Internal SwitchDual BIOSEPU, TPUOC Trigger, BIOS Mode, BIOS ROM, Slot DisableOC mode, CLK increments,  BIOS ROM, Slot Disable
Diagnostics PanelNumericDual NumericNumericNumeric
Other DevicesSerial COM port, USB PortSerial COM port, USB Port, IEEE1394Serial COM portVoltage check pins
Mass Storage Controllers
Chipset SATA6 x SATA 6Gb/s (Total) Shared w/eSATA, mSATA6 x SATA 6Gb/s (Total) Shared with 1x mSATA6 x SATA 6Gb/s6 x SATA 6Gb/s
Chipset RAID Modes0, 1, 5, 100, 1, 5, 100, 1, 5, 100, 1, 5, 10
Add-In SATA2 x ASM1061 PCIe 4 x SATA 6Gb/s, 1 x eSATA (shared)88SE9230 PCIe x2 4 x SATA 6Gb/s ASM1061 PCIe 2 x eSATA88SE9230 PCIe x2 4 x SATA 6Gb/s2 x ASM1061 PCIe 4 x SATA 6Gb/s,
USB 3.02 x ASM1074 Hub 8 x USB 3.0 PortsASM1074 Hub 4 x USB 3.0 Ports2 x PD720210 Hub(8-ports)2 x ASM1074 Hub 8 x USB 3.0 Ports
Primary LANWGI217V PHYWGI210AT PCIeWGI217V PHYKiller E2205 PCIe
Wi-FiBCM4352 PCIe 802.11ac Dual-Band (2x2; 867 Mb/s)NoneIntel 7260 PCIe 802.11ac Dual-Band (2x2; 867 Mb/s)Intel 2230 PCIe 802.11n Single-Band (2x2; 300 Mb/s)
BluetoothBy 802.11ac ComboNoneBy 802.11ac ComboBy 802.11n Combo
HD Audio CodecALC1150ALC1150ALC898ALC1150
DDL/DTS ConnectDTS ConnectDTS ConnectNoneNone
WarrantyThree YearsThree YearsThree YearsThree Years

Three of the above boards have a fifth PCIe x16 slot, but they're all limited to four x16 cards. Located between the first and third x16 slots, the fifth x16 interface is wired directly to the CPU, bypassing the PEX8747 bridge. Anyone not interested in three- or four-way SLI would be better off buying a less expensive motherboard without the PLX switch, so the folks in the market for these platforms can just go ahead pretending the extra slot isn't even there.

Two of the boards in today’s test offer Intel’s Thunderbolt technology, which pairs DisplayPort graphics and PCIe in a single serial signal. Compatible devices eat into both cable bandwidth and the Z87 Express chipset’s eight PCIe 2.0 lanes however, requiring ASRock and Gigabyte to add yet another PLX bridge, the four-lane PEX8605. Adding storage devices to the mini-DisplayPort connectors forces displays down from 4K-capable to a maximum of 2560x1600, while on-board devices and PCIe x1 slots are similarly made to share bandwidth over the PEX8605.

Thomas Soderstrom
Thomas Soderstrom is a Senior Staff Editor at Tom's Hardware US. He tests and reviews cases, cooling, memory and motherboards.
  • iam2thecrowe
    Am i missing something here? I dont see the point of reviewing 3 and 4 way sli boards and not testing 3 and 4 way sli. Seems rather pointless since any average motherboard will perform well in adobe, productivity etc benches dependent on the cpu....
  • Crashman
    This was really just about finding any board that supports Nvidia's requirements about how that third card is connected. We found some, I overclocked them, now I have enough data to pick a board for the System Builder Marathon. But that only explains why overclocking took priority!

    After spending two days per board on a "one week" article, I couldn't add more tests. The general benchmark set looks for unintended overclocking/underclocking, power and memory bandwidth issues, so you can see the performance difference attributable to each board's CPU and DRAM configuration differences. It runs from a .bat file, so it didn't add significantly to the article's completion time.

    The PLX bridge that these all share represents the "great equalizer" when it comes to CrossFire and SLI configuration, so that portion of all three boards should be identical. I understand that things that should be the same in theory are occasionally different in practice. My apologies for not having the extra 1-day per board for additional tests.
  • iam2thecrowe
    12341788 said:
    They all use the same PLX bridge, so you would have seen a whole bunch of identical gaming results. The general benchmark set looks for unintended overclocking/underlocking, power and memory bandwidth issues, so you can see the actual performance difference. And there's still an overclocking section.

    These boards had to be tested for general performance and stability like any other boards. The PLX controller is the equalizer when it comes to games.

    I think testing 3/4 way sli would still be valid, as it doesn't always work properly, in the past there have been compatibility problems with certain gpu's/boards/firmware/controllers and certain benchmarks completely failed.
  • Kraszmyl
    "internally-mounted external USB 2.0 port for ReadyBoost fanatics" on the asus z87.

    Those have nothing to do with readyboost. The internal usb ports are very common on workstations and you put CAD dongles and equivalent items in them so that you can lock them inside the case and don't have to worry about some one stealing them from the outside or them taking up an outside usb port.
  • Memnarchon
    I would love to see Asus Maximus VI Extreme, but it seems ASUS didn't want to give a 2nd board and prefered the Z87 WS....
  • markaflias
    Where are the sli/cfx tests ? Non sense
  • west7
    no cfx test i think the review title is misleading
  • Traciatim
    where are the sli/crossfire benchmarks and comparisons with traditional non-switched setups?

    Hey guys, we have these awesome new setups for supreme graphics pumping power! Watch it zip files like every other board!
  • chumly
    Those heatsinks on the Asus look like the would interfere with large CPU coolers.
  • duramax08
    Why are they still making motherboards with PS/2 connections? Its time to move on, replace those baby's with some USB 3.0!