Intel Kaby Lake Performance: Surprising Jump over Skylake

Content Creation and Gaming

Up next we want to look at a few of the more traditional CPU benchmarks we have used at PC Perspective for a number of years. Both POV-Ray and Blender are 3D rendering applications that content creators are quite used to while the inclusion of the x264 5.0 benchmark will help consumers judge the impact on video transcode times.

POV-Ray

The raw compute performance of this long-form workload sees an impressive 18% performance advantage on the Kaby Lake system compared to Skylake. With a modest 8-10% increase in clock speed at the base frequency (2.7 GHz vs 2.5 GHz) we expected the result to fall inside that range. However, the processor was able to run at closer to the peak Turbo clock for a larger portion of the testing.

Blender 2.78a

While I have used Blender testing before, I am reintroducing it here to prepare for an onslaught of CPU testing in the near future. Using the latest public version of the software and a couple of demo workloads from the Blender performance page, I compared the time to render these scenes on both systems.

This is where we start to see the balance of clock speed coming into the results. The 7^th Generation Core i7-7500U is able to render the BMW example scene 11% faster than the Core i7-6500U and Gooseberry scene 12% faster. Considering that these have VERY long render times (33 minutes for the BMW test and 250 minutes for the Gooseberry) the results are again more impressive than many will expect. With no IPC improvements on the CPU architecture, these changes are purely in the process technology and platform implementation.

X264 5.0 Encoding

Finally we come to the video transcoding performance test; results are simple, higher frame rates are better.

In pass 1, responsible for scanning the entire video file and preparing the workload for better quality, runs 21% faster on Kaby Lake than Skylake, a dominating win in a very common workload. Pass 2 uses that prepared data from pass 1 to better write the final file and here we see a more expected 10% increase in performance for the 7^th Generation processor.

Gaming Testing

Though we understand that the fundamental architecture of the Intel HD Graphics 620 and the 520 are identical (EU counts, etc.) there do appear to be some performance improvements in our basic gaming tests as well.

3DMark Sky Diver

3DMark Sky Diver is a DirectX 11 benchmark for gaming laptops and mid-range PCs. Use 3DMark Sky Diver to benchmark systems with mainstream graphics cards, mobile GPUs, or integrated graphics. It is especially suitable for DirectX 11 systems that cannot achieve more than single-digit frame rates in the more demanding Fire Strike test. Sky Diver is only available in the Windows editions at this time.

A general graphics performance metric, this 3DMark test more suited to the class of GPU we are working with and sees a 13% increase in total performance.

Rocket League and Overwatch

In Rocket League, similar to the result we saw in Sky Diver, the Kaby Lake HD 620 system is 12% faster than the Skylake machine, giving us nearly 60 FPS when running at modest 720p / Quality settings.

Our results in Overwatch give us a 31% improvement in average frame rate when running at 720p and the Medium image quality preset. That number seemed pretty high to me, but I triple ran each test and made sure we were on comparable driver revisions too. It must be a combination of CPU and GPU performance that gives Overwatch the bump in performance, but either way, getting more than 60 FPS in the game on a thin and light convertible notebook is great!

Though the graphics system has the same rated clock window (300 MHz to 1.05 GHz) Intel tells us that with a properly designed thermal system, the operating clock of the GPU portion of Kaby Lake should be consistently higher than that of Skylake.