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.
The 7200RPM drives are all similar in terms of startup current except that the 7K1000.B needs somewhat less than the others on the 5V line. It’s funny with the power-efficient HDDs: the Samsung F2 needs as much power on the 5V line as the “fast” HDDs whereas the others want more! But all of them require less power from the 12V line. Oddly enough, the WD10EADS version P8 has the highest startup current although it has to spin its platters up to 5000 rather than 5400 RPM.
It is good that the HDDs require less and less power in idle mode. WD’s Caviar Black are the only drives to be always ready to work. The others switch into sleep mode. Hitachi’s HDDs have made some great progress. They have always been good in terms of electronics but now their mechanics has become economical as well. As a result, the Hitachi 7K1000.C is the most economical among all the 7200RPM drives. The difference of 2 watts cannot be only due to the loss of one platter. The actuator must have been modernized, too. Samsung’s HDDs show a similar behavior, the F3 being much more economical than its predecessor.
As for the power-efficient products, the Samsung F2 is slower than Western Digital’s HDDs among which the P8 version has the highest consumption despite its 5000 RPM.
When the HDDs have to move their heads about, most of them consume the same amount of power. The Samsung F3 is better than its opponents, which is a very good result considering that its access time is quite competitive among the 7200RPM models. The dual-platter Hitachi 7K1000.C needs as much power as the 3-platter WD Caviar Black, but cannot deliver as low a response time as them.
The power-efficient HDDs take top places. The P8 version WD10EADS consumes somewhat more than the others, again.
The drive’s electronics has to do some work at random writing. As a result, Samsung’s HDDs take top places, being very economical.
The electronics contributes even more to the overall consumption of an HDD at sequential operations: it consumes as much power as the mechanics in the power-efficient models. Take note of the excellent results of the Hitachi 7K1000.C which is as good as the power-efficient HDDs. It seems to have a very effective drive of the platters and also a rather voracious heads actuator. But the heads do not move and consume much at sequential operations.