System Performance

Not all motherboards are created equal. On the face of it, they should all perform the same and differ only in the functionality they provide - however, this is not the case. The obvious pointers are power consumption, but also the ability for the manufacturer to optimize USB speed, audio quality (based on audio codec), POST time and latency. This can come down to manufacturing process and prowess, so these are tested.

Power Consumption

Power consumption was tested on the system while in a single GPU configuration with a wall meter connected to the Corsair HX 750 power supply. This power supply is Platinum rated. As I am in the US on a 120 V supply, leads to ~87% efficiency > 75W, and 92%+ efficiency at 375W, suitable for both idle and multi-GPU loading. This method of power reading allows us to compare the power management of the UEFI and the board to supply components with power under load, and includes typical PSU losses due to efficiency. These are the real world values that consumers may expect from a typical system (minus the monitor) using this motherboard.

While this method for power measurement may not be ideal, and you feel these numbers are not representative due to the high wattage power supply being used (we use the same PSU to remain consistent over a series of reviews, and the fact that some boards on our test bed get tested with three or four high powered GPUs), the important point to take away is the relationship between the numbers. These boards are all under the same conditions, and thus the differences between them should be easy to spot.

Power: Long Idle (w/ GTX 980)

Power: OS Idle (w/ GTX 980)

Power: Prime95 Blend (w/ GTX 980)

Our long idle testing shows the SLI Plus used a couple more watts at idle than the other boards in the list at 71W, and was also close to the Tomahawk Arctic. The OS idle flipped the script a bit and the SLI Plus used the most out of all the boards tested thus far at 74W with the rest coming in at 71, 69, and 68W (Taichi, Tomahawk Arctic and Professional Gaming i9). Last, the load tests show the SLI Plus again using the most power at 240W, while the Tomahawk Arctic is negligibly less. This power difference is due to the board using Multi-Core Turbo/Enhancement and shows in a lot of the subsequent tests. 


Different motherboards have different POST sequences before an operating system is initialized. A lot of this is dependent on the board itself, and POST boot time is determined by the controllers on board (and the sequence of how those extras are organized). As part of our testing, we look at the POST Boot Time using a stopwatch. This is the time from pressing the ON button on the computer to when Windows 10 starts loading. (We discount Windows loading as it is highly variable given Windows specific features.


Post times for the SLI Plus is 29.4 (default) and 28.1 seconds (stripped), which is a middle of the pack results, is about the same as the Tomahawk Arctic and a bit faster than the Gaming Pro Carbon. The ASRock boards still lead the pack by a couple of seconds. 

Rightmark Audio Analyzer 6.2.5

Rightmark:AA indicates how well the sound system is built and isolated from electrical interference (either internally or externally). For this test we connect the Line Out to the Line In using a short six inch 3.5mm to 3.5mm high-quality jack, turn the OS speaker volume to 100%, and run the Rightmark default test suite at 192 kHz, 24-bit. The OS is tuned to 192 kHz/24-bit input and output, and the Line-In volume is adjusted until we have the best RMAA value in the mini-pretest. We look specifically at the Dynamic Range of the audio codec used on board, as well as the Total Harmonic Distortion + Noise.

Due to circumstances currently out of our control, we were unable to get RMAA results for this board. The problem does not lie with the board itself. Once we are able to get it working properly, the space will be updated with data. 

DPC Latency

Deferred Procedure Call latency is a way in which Windows handles interrupt servicing. In order to wait for a processor to acknowledge the request, the system will queue all interrupt requests by priority. Critical interrupts will be handled as soon as possible, whereas lesser priority requests such as audio will be further down the line. If the audio device requires data, it will have to wait until the request is processed before the buffer is filled.

If the device drivers of higher priority components in a system are poorly implemented, this can cause delays in request scheduling and process time.  This can lead to an empty audio buffer and characteristic audible pauses, pops and clicks. The DPC latency checker measures how much time is taken processing DPCs from driver invocation. The lower the value will result in better audio transfer at smaller buffer sizes. Results are measured in microseconds. 

Deferred Procedure Call Latency

DPC Latency is in the expected range, below 300, and comes in second to the Tomahawk Arctic, a few percent faster than the ASRock boards and the Gaming Pro Carbon.  

Benchmark Overview CPU Performance: Short Form


View All Comments

  • Vatharian - Wednesday, November 29, 2017 - link

    Why, why manufacturers won't let the U.2 die? We are already past SATA Express, and now this. I get it, it's one of the most popular connectors to connect SAS backplanes, and most of HBAs and RAID controllers do use it, but please, let it die in desktop space. If anything SFF8087 should remain, as SFF-8639 (U.2) is much flimsier and easier to break.

    Also, we already have far superior standard just behind the corner, in the form of OCuLink.
  • peterfares - Wednesday, November 29, 2017 - link

    Why not have it there though? X299 is a prosumer platform, they may want to use U.2 drives. Reply
  • Lolimaster - Wednesday, November 29, 2017 - link

    x399 laughs at X299 being called "prosumer" 44pci-e lanes vs 64 pci-e lanes, bootable nvme raid support. Reply
  • BillyONeal - Wednesday, November 29, 2017 - link

    I'm a "prosumer" who built both X299 and X399 boxes and couldn't care less about those things. Compiler want MOAR CORRRREEEESSSSSS Reply
  • drajitshnew - Friday, December 1, 2017 - link

    Why call it a prosumer product when it doesn't have ANY m2/u2 connected to the processor? Reply
  • andychow - Wednesday, November 29, 2017 - link

    Doubtful it will disappear. With Optane coming out with only a U.2 connector on the SSD format, it rather insured that U.2 will grow in demand. Reply
  • BillyONeal - Wednesday, November 29, 2017 - link

    The 750 was also like that but didn't spur demand for U.2. The add-in cards are just fine. Reply
  • Dr. Swag - Wednesday, November 29, 2017 - link

    Could you guys do some better vrm testing? X299 vrms have been a hot topic (pun intended) due to Skylake X drawing a lot of power when OCed and because of the addition of up to 18 cores. Some vrms get quite toasty under load so if you guys had good vrm temp measurements and perhaps even measurements on voltage ripple and stuff coming out of the vrm that would be awesome. Reply
  • - Wednesday, November 29, 2017 - link

    And let's not forget measurement of VRM power efficiency to compare the quality of VRMs across motherboards! Reply
  • Lolimaster - Wednesday, November 29, 2017 - link

    Just but Threadripper and forget about those problems. Reply

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