ASRock X99 Extreme6/ac Motherboard Review

Featuring the same wireless controller as its closest competitor, ASRock’s X99 Pro adds a second gigabit Ethernet controller and removes a few pathway sharing issues. Have we finally found a value-winning solution for high-end LGA 2011-v3 buyers?

Early Verdict

Similar in many ways to the Asus X99 Pro, ASRock’s $15-cheaper X99 Extreme6/ac appears to be worth exactly $15 less than that competing product.

Pros

  • +

    The X99 Extreme6/ac includes Broadcom’s high-end 802.11ac Wi-Fi / BT 4.0 module.

Cons

  • -

    The lack of PCIe lane switches make the X99 Extreme6/ac a 2-way SLI board with 3-way SLI potential.

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The Lane Games

More PCI Express connectivity is one of the most prominent reasons to buy an LGA 2011-v3-based platform. Lots of CPU cores are important to certain power users as well, but those PCIe lanes and the four-channel memory controller are why the processor interface is so much larger than Intel's mainstream LGA 1150.

This is a motherboard review after all, and it’s easy for those of us who need extra pathways to see that 40 lanes of PCIe 3.0 are twice as many as 20. Intel even says that 2011-v3’s lanes can be divided across five slots, compared to LGA 1150’s three.

But the tech specs get more complicated after that, and the struggle against those complications are where we often see great ideas fall apart. The first problem is that Intel reserves the 40-lane PCIe 3.0 controller for its top two Core i7 models (currently, the -5960X and -5930K). Lower models like the -5820K get a 28-lane controller. Yet, even with only 28 lanes, we should be able to get three-way SLI at x8-x8-x8 and have four lanes leftover for a PCIe 3.0 x4 SSD, right?

Swipe to scroll horizontally
ASRock X99 Extreme6/ac
PCB Revision1.07Voltage Regulator12 Phases
ChipsetIntel X99100.0 MHz BCLK99.94 (-0.06%)
I/O Panel Connectors
P/S 21CLR_CMOS Button1
USB 3.06Digital Audio OutOptical
USB 2.02Digital Audio InNone
Network2Analog Audio5
eSATA1Other Devices2x Wi-Fi Antenna
Internal Interfaces
PCIe 3.0 x16 (-5960X, -5930K)3 (x16/x16/x8) SLI x3, CrossFire x3 M.2 disables x8 slotPCIe 3.0 x16 (-5820K)3 (x16/x8/x4) SLI x2, CrossFire x3 M.2 disables x4 slot
4-Pin Fan23-Pin Fan4
PCIe 2.0 x16NonePCIe 2.0 x12 (+1x Mini PCIe, Filled)
FP-Audio1S/PDIF I/ONone
USB 3.02 (4-ports)USB 2.02 (4-ports)
Internal ButtonsPower, ResetInternal SwitchDual BIOS Selector
SATA 6.0 Gb/s10 (Shares eSATA, M.2)SATA ExpressNone
Diagnostics PanelNumericOther ConnectorsCOM, TB_Header, HDD-Saver, USB Type-A
Mass Storage Controllers
Chipset SATA10x SATA 6Gb/s (Includes M.2, eSATA)Add-In SATANone
Chipset RAID Modes0, 1, 5, 10 (Ports 1-6)USB 3.0ASM1042e PCIe ASM1072 Hub
Networking
Primary LANWGI218V PHYSecondary LANAR8171 PCIe
Wi-FiBCM4352 PCIe 802.11ac dual-band / BT 4.0BluetoothBT 4.0 / Wi-Fi Combo
Audio
HD Audio CodecALC1150DDL/DTS ConnectDTS Connect
WarrantyThree YearsPrice$295

In unfortunate mimicry of its closest competitor, ASRock doesn’t split the first slot into x8 mode, even when the lanes are needed elsewhere. Perhaps this is a marketing decision. Or perhaps the engineers just wanted to save a few dollars in PCIe pathway switches. At any rate, the X99 Extreme6/ac bears the same three-way SLI caveats as the recently-reviewed Asus X99 Pro. The Core i7-5820K processor breaks three-way SLI capability, and a PCIe-based M.2 drive disables that slot entirely. The good news for those whose hardware choices are unaffected is that—unlike its long-divorced partner—ASRock didn’t screw up the X99 Extreme6/ac’s PCIe 2.0 slots.

ASRock’s always tried to offer its customers a few more features for a little less money, so let’s see what other advantages the X99 Extreme6/ac holds…

Thomas Soderstrom
Thomas Soderstrom is a Senior Staff Editor at Tom's Hardware US. He tests and reviews cases, cooling, memory and motherboards.
  • vertexx
    Still looking for the value X99 board without too many trade-offs. What would be helpful for me is a chart comparing the x99 board with the various slot/lane options for the 5820 vs. 5930/5960 CPUs.
    Reply
  • JeanLuc
    You haven't shown any results for the SATA and ESATA throughput, the USB controllers transfer speeds (Intel speeds I would guess are the same across the board but what the 3rd party controllers?).

    Anyone who is buying this will also want to know how good the wireless AC and bluetooth that have been bundled with the motherboard are.

    How good is the sound chip? Can you hear background static when you have earphones plugged in if so how bad? Has the manufacturer made any effort to isolate background noise and how effective are those measures?

    There is so much you have missed in this "review".
    Reply
  • Crashman
    15149683 said:
    Still looking for the value X99 board without too many trade-offs. What would be helpful for me is a chart comparing the x99 board with the various slot/lane options for the 5820 vs. 5930/5960 CPUs.
    Right now Gigabyte has the best lane configuration and slot spacing four four cards, MSI has the best lane configuration and slot spacing for three. Gigabyte has the USB 3.0 header blocked by a fourth card, MSI has the three cards + PCIe x4 M.2 +USB 3.0 configuration nailed (if you care about PCIe x4 M.2). You'll see another MSI board in a review still pending its publishing date.
    Reply
  • Crashman
    15149944 said:
    You haven't shown any results for the SATA and ESATA throughput, the USB controllers transfer speeds (Intel speeds I would guess are the same across the board but what the 3rd party controllers?).

    Anyone who is buying this will also want to know how good the wireless AC and bluetooth that have been bundled with the motherboard are.

    How good is the sound chip? Can you hear background static when you have earphones plugged in if so how bad? Has the manufacturer made any effort to isolate background noise and how effective are those measures?

    There is so much you have missed in this "review".
    That's it, I'm asking Adam Overa to find a controller tester :) We should have a collection of standard controller test results to link when discussing the inclusion of these parts on a motherboard.

    Reply
  • vertexx
    15153170 said:
    Right now Gigabyte has the best lane configuration and slot spacing four four cards, MSI has the best lane configuration and slot spacing for three. Gigabyte has the USB 3.0 header blocked by a fourth card, MSI has the three cards + PCIe x4 M.2 +USB 3.0 configuration nailed (if you care about PCIe x4 M.2). You'll see another MSI board in a review still pending its publishing date.

    That about summarizes it - thanks! I'm looking at a 5820k based rig. Long term goal is water-cooled 3-way x8 + PCIe x4 M.2. So, MSI has that configuration down. Shorter term would more realistically be air-cooled 2-way, and my understanding is the MSI is not the best for 2-way air cooled due to the slot spacing.

    So I think I'm looking for a board that can do both a (1) dual SLI x16/x0/x8 + x4 M.2 or (2) 3-way SLI x8/x8/x8 +x4 M.2, all at just above $200.

    The lowest price board I could find that can do this is the ASRock x99 Fatal1ty Pro or OC Formula, both in the $340-350 price range. The Professional happens to have a $40 rebate plus $85 DDR4 combo discount, making this a ~$220 proposition for this board. Tempting......
    http://www.newegg.com/Product/Product.aspx?Item=N82E16813157539
    Reply
  • Crashman
    15154249 said:
    15153170 said:
    Right now Gigabyte has the best lane configuration and slot spacing four four cards, MSI has the best lane configuration and slot spacing for three. Gigabyte has the USB 3.0 header blocked by a fourth card, MSI has the three cards + PCIe x4 M.2 +USB 3.0 configuration nailed (if you care about PCIe x4 M.2). You'll see another MSI board in a review still pending its publishing date.

    That about summarizes it - thanks! I'm looking at a 5820k based rig. Long term goal is water-cooled 3-way x8 + PCIe x4 M.2. So, MSI has that configuration down. Shorter term would more realistically be air-cooled 2-way, and my understanding is the MSI is not the best for 2-way air cooled due to the slot spacing.

    So I think I'm looking for a board that can do both a (1) dual SLI x16/x0/x8 + x4 M.2 or (2) 3-way SLI x8/x8/x8 +x4 M.2, all at just above $200.

    The lowest price board I could find that can do this is the ASRock x99 Fatal1ty Pro or OC Formula, both in the $340-350 price range. The Professional happens to have a $40 rebate plus $85 DDR4 combo discount, making this a ~$220 proposition for this board. Tempting......
    http://www.newegg.com/Product/Product.aspx?Item=N82E16813157539
    Please consider our first roundup:
    http://www.tomshardware.com/reviews/intel-x99-haswell-e-overclocking,3934.htmlIt has 2nd-tier (price-range) X99 motherboards with Gigabyte, ASRock and MSI compared, and it has the PCIe stuff you're looking for. In regards to the 5820K, MSI has "4 (x16/x8/x0/x4*, x8/x8/x8/x4*) *Forces M.2 to PCIe 2.0 x2" What this means is that the fourth slot is shared between M.2 and "PCIe x16 slot 4" I believe MSI's entire X99 range is made the same way, apart from the boards that have a PCIe 48-lane switch.

    So MSI gets you 3-way + an x4 M.2. Most people are only interested in 2 way SLI as a future upgrade, and ASRock does 2-way + an x4 M.2.

    It could be a while before we get down to the lowest X99 pricing tier, but expect coverage of MSI's cheap X99 board in "some other kind of article" three weeks from now.
    Reply
  • Ekroen
    Seems to be good.
    Reply