| State | DC measured<br>power consumption | AC calculated<br>power consumption | Remarks |
|---|---|---|---|
| Idle | 5.4 W | 6.2 W | |
| CPU Load | 10.8 W | 12.4 W | stress-ng (all cores) |
**Full Kit (with 5x HDDs)**
| State | DC measured<br>power consumption | AC calculated<br>power consumption | Remarks |
|---|---|---|---|
| Idle | 25.2 W | 29 W | |
| CPU Load | 31.2 W | 35.9 W | stress-ng (all cores) |
| HDD Read | 36 W | 41.4 W | dd read (no caching) from RAID6 array|
| HDD Write | 34.8 W | 40 W | dd write (no caching) to RAID6 array |
| Network Access | 33.6 W | 38.6 W | HTTP download from RAID6 array |
| Stress Test | 40.8 W | 47 W | stress-ng (all cores) + fio (all disks) + iperf |
!!! note
Measures were done using a Current Clamp Meter on the Helios64 12V DC input. AC Power consumption is calculated based on a AC/DC conversion efficiency of 85%.
* Meter tool : Extech 380942 - 30A True RMS AC/DC Mini Clamp
* AC/DC Adapter : 12V 10A (efficiency : 85%)
* HDD: 5x Toshiba P300 1TB (HDWD110) configured as RAID6
* Network : Connected at 2500Mb/s
* Fan : Medium speed (PWM 100)
* Battery : Charge status 100%
* OS: Armbian Ubuntu (Bionic) Linux 4.4.213-rk3399
**Power consumption depends a lot on the HDDs brand and model used.**
## HDD Recommendation
We recommend HDD which are designed for NAS (Network Attached Storage). Those NAS HDD are specially conceived for reliable 24/7 operation and offers lower power consumption and dissipation, less vibration and noise, and finally better warranty. We recommend the following brands / families :