Zotac ZBOX CA320 nano PLUS Review: A Fanless AMD mini-PC

Power Consumption and Thermal Performance

The power consumption at the wall was measured with a 1080p display being driven through the HDMI port. In the graphs below, we compare the idle and load power of the Zotac ZBOX CA320 nano with other low power PCs evaluated before. For load power consumption, we ran Furmark 1.12.0 and Prime95 v27.9 together. The numbers are not beyond the realm of reason for the combination of hardware components in the machine.

We do find that the idle power consumption is lower than the ZBOX CI540 nano, but it doesn't match the numbers set by the ECS LIVA. As expected, the load power consumption tracks the inherent capabilities of the CPU in the system.

We evaluated the thermal performance from a system perspective.  We start with the system at idle, followed by 30 minutes of pure CPU loading. This is followed by another 30 minutes of both CPU and GPU being loaded simultaneously. After this, the CPU load was removed, allowing the GPU to be loaded alone for another 30 minutes. The various clocks in the system as well as the temperatures within the unit are presented below.

At the outset, it must be said that we didn't observe any throttling in action. The CPU cores are advertised for 1 GHz and they maintain that frequency throughout the pure CPU loading stage. The GPU cores idle around 200 MHz. After the GPU load kicks in, the Radeon HD 8250 cranks up to 400 MHz, while the CPU cores move down to the 800 - 900 MHz (and occasionally up to 1 GHz) range to obey the TDP limits. After removal of the CPU load, the cores dial down to 200 MHz (just cranking up once in a while). On the temperature side of things, the core and GPU track each other closely. The junction temperature is around 90 C, and the maximum temperature we encountered in our stress test was slightly above 80 C. Idling temperature was around 50 C.

Another important aspect to keep note of while evaluating fanless PCs is the chassis temperature. Using Seek Thermal's thermal imager, we observed the chassis temperature after the CPU package temperature reached the steady state value in the above graph.

Surprisingly, the chassis temperature reached only 56 C after full loading. Compared to the 75 C+ that we saw with the ZBOX CI540 nano, this is really cool. Some of the other thermal pictures we took of the unit after the full loading process are reproduced in the gallery below.