You can refer to our article called Hard Disk Drive Power Consumption Measurements: X-bit’s Methodology in Depth for details on this test. We will just list the specific modes we measure the power consumption in:
- Start (the current the drive consumes when starting up)
- Idle (the drive is not accessed at all, but it is turned on and ready to work)
- Random Read and Write
- Sequential Read and Write
Let’s check out each mode one by one.
When it comes to starting up, the HDDs have a rather standard power draw on the 5V line. As opposed to that, they consume a very low current from the 12V line. Unlike HDDs for notebooks, high-performance SAS products cannot do without 12V, though.
The Seagate 10K.1 is poor in comparison with the others. It needs a 50% higher current than what the other HDDs require. Even the 15,000rpm model needs less. The Hitachi C10K300 and the Fujitsu look best in this test, just like in many previous ones.
We’ve got one leader under low load. It is the Fujitsu and it has the most economical mechanics. Second place goes to the Seagate 10K.2 which has the most economical electronics. The Hitachi drives are not very good here. They have very voracious mechanics and their electronics is not exactly economical, either.
These compact HDDs look excellent in comparison with 3.5-inch counterparts and consume only half as much power.
The small diameter of the platters and the reduced heads (but rather fast heads nonetheless) produce considerable benefits when it comes to reducing power consumption. The random reading of the best products, the Seagate 10K.2 and the Hitachi C10K300, fits within 6.5 watts. The Seagate 15K.1 with 15,000rpm platters fits within 8 watts while its full-size opponents need up to two times as much as it.
Take note that the consumption of the electronics contributes a lot to the overall result of compact SAS drives in this test. The Seagate 10K.2 consumes more from the 5V line than from the 12V one. The other models consume about the same amount of power from both lines.
The overall picture remains the same when we switch from random reading to random writing. The HDDs all consume the same amount of power from both lines, and the newer models are superior to the older ones in terms of power efficiency.
It is more interesting at sequential reading. The read/write heads do not have to move so actively and the 12V consumption is lower while the electronics works heavily at sequential operations. We can note that each new generation of HDDs have both more economical electronics and mechanics. The overall standings are the same: the Hitachi C10K300 and the Seagate 10K2 are in the lead while the old Hitachi C10K147 and Seagate 10K.1 are the most voracious drives in this test.
Take note that the Seagate 15K.1 is quite comparable to the 10,000rpm drives in terms of power consumption.
When we switch from sequential reading to sequential writing, the overall picture still remains the same: newer HDDs need less power and the drives mostly consume from the 5V line, i.e. with their electronics.