We tested the peak power consumption of a NAS at the wall during a run of CrystalDiskMark 5.0.2 as this version of the benchmark runs the read and write benchmark suites separately so its easier to monitor what power the device is using during each function.
Synology quote a 28.8W power access figure for the DiskStation DS918+ using four 1TB WD Red (WD10EFRX) drives. For testing purposes we used four WD Red 6TB drives which are a bit more power hungry at 5.3W (active read/write) than the 3.3W active figure for the 1TB version of the Red.
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