ASRock X370 Killer SLI/ac Motherboard Review

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Benchmark Results

Synthetics

The Killer SLI/ac gets hit right off the bat with some unfortunate PCMark losses, lagging behind the pack by a whopping six percentage points (from the leader). However, the remainder of the Sandra synthetics are showing much closer comparisons across the samples, with the Killer winning memory bandwidth, crypto, and arithmetic workloads.

Unfortunately, the Compubench FaceDetect workload shows atypical results compared to my previous samples. Our data does line up with Compubench’s aggregate average for the GTX 970, so retests are needed to confirm repeatability. Performing a fresh install of the operating system and updating Windows and drivers to appropriate levels still shows repeatable Compubench outcomes. It would be interesting to compare some of the previous hardware with the latest Windows updates to confirm whether driver updates are the culprit.

This trend continues in the 3DMark suite, where the combined scores are comparable to other review samples, but graphic scores trail by up to five percentage points within the Skydiver benchmark. Cranking up to Firestrike Extreme evens the playing field and helps shift the focus from the board and processor to the graphics card alone.

Timed Applications

The application data was less than interesting from our perspective, showing a very narrow delta across samples such that any explanation would likely be in the margin of error. The only application of note is in 7-Zip, where the Killer SLI/ac finishes the job eight seconds before our previous leader and laughs on the sideline as its brother, the ASRock X370 Gaming K4, huffs and puffs across the finish line 43 seconds later. 

Overall, a mixed success for the ASRock X370 Killer SLI/ac is only compounded by driver issues in the graphics department. Hopefully, this is only evident in the synthetics portion and the games will show the true story.

3D Games

To reiterate, the ASRock X370 Killer SLI/ac ushers in the era of true 4K gaming in my test suite, so any old 3460x1920 data represented here will clearly favor the products tested in older reviews. However, we will include it here for both academic and comparison purposes to see how this combo fairs against the older 40” triple monitor setup. True 4K data will be denoted with asterisks. 

Standard Ashes of the Singularity at 1080p sets the stage for the comparisons today by showing that driver issues observed during the synthetics are no longer an issue. The High setting is still playable at all batch conditions for all systems, and Crazy settings favor the MSI Krait Gaming by nearly two frames when compared to the Killer SLI/ac. Increasing the resolution to true 4K on the Killer shows acceptable framerates across all batch conditions with high settings, and increasing the pixel count by roughly 25% only impacts performance by 10%. Even at Crazy settings, true 4K is still equally as unenjoyable as with the other samples. Note we did collect Escalation data for this sample, and will begin publishing that data in the next review. Also, we collected 1440p data, so sit in anticipation as that comes.

Yawn. F1 2015 throws the Killer SLI/ac into the middle of the pack at 1080p. We are hit by a jump scare as 4K ultra presets show that the increase in pixels drops performance by 24%, which scales nicely pixel-for-pixel. We would anticipate that this sample would perform right in line with the previous samples at the Nvidia Surround resolution of 3460x1920.

The Talos Principle takes a strange twist from the previous benchmark and shows the ASRock Killer SLI/ac leaping past the competition with a four-percentage point lead compared to the Biostar GT7 at 1080p. Even more interesting is that the increased pixel count actually shows little impact at 4K, empowering similar leads for the Killer SLI/ac. Would 3460x1920 have made the delta even larger, or does this game really just not stress this GPU enough?

Metro Last Light Redux shows similar trends compared to Ashes in that at 1080p all samples are running neck-and-neck when comparing average framerates. That 4K resolution though. Framerate impact scales fairly well and a 20% performance impact is observed across both detail settings; 4K is only recommended at lower details with the GTX 970.

Gaming on a true 4K monitor with the ASRock X370 Killer SLI/ac feels the same as our previous samples, and the addition of the contiguous monitor real estate is worth the decrease in frames across games. We could perform some statistical manipulation to this data to more directly compare these products with pure numbers, but we think the Killer SLI/ac is still doing well against the benchmarks.


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