Zotac ZBOX CI320 nano Review: A Fanless Bay Trail-M mini-PC

HTPC Credentials

The absence of any moving parts inside the ZBOX CI320 nano enables a completely silent PC irrespective of the workload. This makes it an ideal HTPC. While acoustics form one part of the HTPC story, there are a few other aspects that we will cover in this section.

Refresh Rate Accurancy

AMD and NVIDIA have historically been able to provide fine-grained control over display refresh rates. The default rates are also quite accurate. Intel used to have an issue with 23 Hz (23.976 Hz, to be more accurate) support, but that was resolved with the introduction of Haswell and Bay Trail. As expected, the Zotac ZBOX CI320 nano has no trouble with refreshing the display appropriately in the 23 Hz setting.

The gallery below presents some of the other refresh rates that we tested out. The first statistic in madVR's OSD indicates the display refresh rate.

Network Streaming Efficiency

Evaluation of OTT playback efficiency was done by playing back our standard YouTube test stream and five minutes from our standard Netflix test title. Using HTML5, the YouTube stream plays back a 720p encoding, while Adobe Flash delivers a 1080p stream. Note that only NVIDIA exposes GPU and VPU loads separately. Both Intel and AMD bundle the decoder load along with the GPU load. The following two graphs show the power consumption at the wall for playback of the HTML5 stream and the Adobe Flash stream in Mozilla Firefox (v 33.1.1). The Flash plugin version used for benchmarking was 15.0.0.223. GPU load was around 33.05% for the HTML5 stream and 22.53% for the Flash stream.

Netflix streaming evaluation was done using the Windows 8.1 Netflix app. Manual stream selection is available (Ctrl-Alt-Shift-S) and debug information / statistics can also be viewed (Ctrl-Alt-Shift-D). Statistics collected for the YouTube streaming experiment were also collected here. GPU load in the steady state for the Netflix streaming case was 3.58%.

Decoding and Rendering Benchmarks

It is quite clear that passively cooled UCFF PCs such as the CI320 nano are not madVR-capable machines. Hence, we concentrate on local file playback using EVR-CP and Kodi. The decoder used was LAV Filters bundled with MPC-HC v1.7.7

The CI320 nano was able to pass all our test streams using decoders / renderers that the average consumer would use. Even the 4Kp30 H.264 stream decoded without frame drops and was output on to a 1080p display without issues. The only caveat is that HD audio bitstreaming is not enabled on these Bay Trail boxes under Windows, but works without issues in Linux. On a side note, this doesn't affect Dolby Digital Plus bitstreaming from the Netflix app. In our opinion, this would make a great little OpenELEC box or Ubuntu / XBMC system.