Exploring Thunderbolt 3 eGFX Performance, Feat. PowerColor's Gaming Station & Radeon RX Vega 56 Nano

UL 3DMark and VRMark

UL's 3DMark comes with a diverse set of graphics workloads that target different Direct3D feature levels. Correspondingly, the rendering resolutions are also different. The VRMark benchmark targets virtual reality specifically. Its workloads are termed as 'rooms', with each one being a piece of VR content designed to require a specific level of VR performance. We used 3DMark 2.4.4264 and VRMark 1.2.1701 to get an idea of the graphics capabilities of various systems. In this section, we take a look at the performance of the Zotac MI553 eGPU on a comparative basis across the different workloads.

3DMark Ice Storm

This workload has three levels of varying complexity - the vanilla Ice Storm, Ice Storm Unlimited, and Ice Storm Extreme. It is a cross-platform benchmark (which means that the scores can be compared across different tablets and smartphones as well). All three use DirectX 11 (feature level 9) / OpenGL ES 2.0. While the Extreme renders at 1920 x 1080, the other two render at 1280 x 720. The graphs below present the various Ice Storm worloads' numbers for different systems that we have evaluated.

The Ice Storm series of benchmarks is not entirely suited for our test configurations. Benchmark scores above 40000 are quite sensitive to non-GPU factors. As such, those workloads are too simple for the configuration.

3DMark Cloud Gate

The Cloud Gate workload is meant for notebooks and typical home PCs, and uses DirectX 11 (feature level 10) to render frames at 1280 x 720. The graph below presents the overall score for the workload across all the systems that are being compared.

Cloud Gate shows the Shuttle internal GPU configuration coming out on top, as expected. The eGPU solution involving Bean Canyon surprisingly outsmarts the other configurations, showing that this benchmark benefits from CPU power rather than just the PCIe link width.

3DMark Sky Diver

The Sky Diver workload is meant for gaming notebooks and mid-range PCs, and uses DirectX 11 (feature level 11) to render frames at 1920 x 1080. The graph below presents the overall score for the workload across all the systems that are being compared.

The Sky Diver benchmark results are similar to that of Cloud Gate.

3DMark Fire Strike Extreme

The Fire Strike benchmark has three workloads. The base version is meant for high-performance gaming PCs. Similar to Sky Diver, it uses DirectX 11 (feature level 11) to render frames at 1920 x 1080. The Ultra version targets 4K gaming system, and renders at 3840 x 2160. However, we only deal with the Extreme version in our benchmarking - It renders at 2560 x 1440, and targets multi-GPU systems and overclocked PCs. The graph below presents the overall score for the Fire Strike Extreme benchmark across all the systems that are being compared.

This benchmark sees the two internal GPU solutions on top, indicating that the workload is sensitive to the bandwidth between the host CPU and the GPU (PCIe 3.0 x16 vs. x4 in the other configurations).

3DMark Time Spy

The Time Spy workload has two levels with different complexities. Both use DirectX 12 (feature level 11). However, the plain version targets high-performance gaming PCs with a 2560 x 1440 render resolution, while the Extreme version renders at 3840 x 2160 resolution. The graphs below present both numbers for all the systems that are being compared in this review.

The Time Spy benchmarks are similar to the Cloud Gate and Sky Diver benchmarks in terms of the ordering of the performance of different configurations. Here, the CPU capabilities are more important than the available host-GPU bandwidth.

The VRMark Professional Edition v1.2.1701 comes with three rooms. Each room can be run either in desktop or HMD mode, with varying minimum requirements for the same workload. The benchmark results include the average FPS achieved, and a score based on the FPS. A pass or fail indicator is also provided based on whether the average FPS exceeds the required FPS. In this section, we take a look at the performance of the Zotac MI553 eGPU on a comparative basis across the three workloads in desktop mode.

VRMark Orange Room

The Orange Room is meant to test the effectiveness of a system for handling the requirements of the HTC Vive and the Oculus Rift. The recommended hardware for both VR HMDs should be able to easily achieve the desired target FPS (88.9 fps). However, in the desktop mode, the target performance is 109 fps without any frame drops. Systems benching with an average FPS lesser than that are deemed to have failed the VRMark Orange Room benchmark. The graphs below present the average FPS and score for the different systems being considered today.

The PowerColor Radeon RX Vega 56 Nano is easily able to pass the VRMark Orange Room test as an eGPU even with an ultrabook as the host.

VRMark Cyan Room

The Cyan Room sits between the Orange and Blue rooms in complexity. It is a DirectX 12 benchmark. Similar to the Orange room, the target metrics are 88.9 fps on HMDs and 109 fps on the desktop monitor. The graphs below present the average FPS and score for the different systems being considered today.

The PowerColor Radeon RX Vega 56 Nano is easily able to pass the VRMark Cyan Room test as an eGPU even with an ultrabook as the host.

VRMark Blue Room

The Blue Room is the most demanding of the three workloads. At the time of introduction of VRMark in October 2016, no publicly available system running as sold was able to pass the test. The performance of a system in this benchmark is an indicator of its VR-readiness for future generation of HMDs. Similar to the other workloads, the passing performance metrics are 88.9 fps on HMDs and 109 fps on desktop monitors. The complexity of the workload is due to the higher resolution (5012 x 2880) and additional geometry making it necessary to increase the number of Direct3D API calls. The graphs below present the average FPS and score for the different systems being considered today.

The PowerColor Radeon RX Vega 56 Nano can not pass the VRMark Blue Room test with any of the tested host systems.