Graphics Performance and Thermal Throttling
Gaming performance is obviously one of the biggest marketing points of the ROG Zephyrus, so we decided to put it through our normal workload of GPU benchmarks.
In these tests, we are comparing the Max-Q GTX 1080 found in the Zephyrus with its GTX 1080 and 1070 desktop counterparts to validate the claim of "GTX 1080-level performance" in these smaller form factor machines.
We are using our Frame Rating testing methodology for these tests, just as we do for all of our GPU reviews. For more information on the methodology, you can consult this article explaining the entire process.
We are performing all of our tests at 1080p, the native resolution of the Zephyrus's display.
Our Dirt Rally results at Ultra settings puts the Zephyrus's performnace between the desktop GTX 1080 and the GTX 1070, with the 50th percentile FPS trending more towards the GTX 1070. Additionally, we find higher frame variance with the Max-Q GPU though they are under 2ms at the 95th percentile indicating a smooth gaming experience.
Grand Theft Auto V
In GTA V, we see an interesting scenario play out. At 1080P with Very High settings, the GTX 1080 and 1070 perform almost identically on our GPU testbed. However, when we look at the Max-Q result compared to these two, it is substantially lower. This is likely due to the differences in CPU between our desktop PC and the Zephyrus. The mobile i7-7700HQ struggles with GTA V's demands.
Our first DX12 game in these results, Hitman at Ultra settings shows the GTX 1080 in the Zephyrus to be closer to the desktop GTX 1070 than the 1080. Frame time variance also sees an almost 2ms increase when moving to the Max-Q GPU in the Zephryus though it is still in a reasonable range.
Rise of the Tomb Raider
When playing Rise of the Tomb Raider in DX12 mode and ultra settings, we see the Max-Q 1080 performing much closer to the desktop GTX 1080 in average FPS. However, the 95th percentile frame variance is about 3-4x higher than the desktop GPUs. Hittin the 5ms+ mark indicates more judder than we would like to see.
The Witcher 3
Once again, The Witcher 3 at Ultra settings show the Zephyrus to perform much closer to a desktop GTX 1070 than 1080. However, frame variance is more in line with the desktop GPUs than in most of the other games.
Overall, the GTX 1080 with Max-Q design seems to perform closer to a desktop GTX 1070 than a GTX 1080. This makes the GTX 1080 branding at best meaningless and at worst disingenuous to the actual performance of the GPU. But this has been the case for mobile variants of graphics hardware for many generations. NVIDIA claimed to eradicate that mentality with the GTX 10-series mobile product launch, but the thermal and power limits of these form factors are clearly having an impact.
Also, as we would expect with a thermally limited design, the frame variance is higher in the Zephyrus than we would expect from this same silicon in its larger desktop counterparts.
It's worth noting that from an experiential standpoint, I feel that all of these games were in a playable state. While you might have some occasional frame stutter, overall these games look beautiful and smooth on the 120Hz G-Sync display in the Zephyrus.
To further test the thermal capabilities of the Zephyrus, we decided to run a more long-term gaming test. While most of our GPU benchmarks take place for just 60 seconds, we decided to keep a game running for a longer period and compare the benchmark results of the beginning and end runs.
For this expanded testing, we turned to Dirt Rally's benchmark mode. This mode is very close to real world performance while racing, just with an AI controlled driver instead of user input. Additionally, a loop setting can be enabled, allowing us to walk away so the notebook gets nice and toasty in a consistent manner.
We ran Dirt Rally at the same 1080p Ultra settings as above and gathered our normal 60-second benchmark run. Then, we continued to let the same loop in benchmark mode for an additional 45 minutes and then did another benchmark run.
The results are impressive. Despite gaming for a solid 45 minutes, the ASUS ROG Zephyrus performed nearly identically in the two benchmark results. This speaks well to the consistency of the thermal experience with the Zephyrus. Gamers shouldn't worry about their game slowing down as they engage in extended gameplay sessions.