You can refer to our article called Hard Disk Drive Power Consumption Measurements: X-bit’s Methodology Indepth 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 speeding up its spindle)
- 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 3-platter Hitachi 5K500 differs from the others with its high power consumption during startup. It needs over 1 ampere from the +5V line. Hitachi’s new 5K500.B series drive is, on the contrary, the most economical.
The HDDs differ greatly in terms of power consumption in idle mode. The Seagate 7200.4 proves to be the most voracious because it needs more energy to maintain the higher speed of its two platters than the 3-platter 5400rpm models. The Seagate 5400.6 and Western Digital are not much more economical, though. It is the new Hitachi 5K500.B and the Fujitsu MJA2 that really have a modest appetite.
The HDD from Toshiba proves to be the most economical under random loads. It is the best both at reading and writing. Second place is shared by the new products from Hitachi and Samsung. The Travelstar 5K500.B is more economical at reading while the SpinPoint M7, at writing. It is the Hitachi 5K500 and Samsung M6 that are the most voracious in this test. Each of them has three platters and six heads. Even the 7200rpm Seagate 7200.4 needs less power thanks to its 2-platter design.
It is interesting to compare the Seagate HDDs. The 5400rpm model consumes about the same amount of power at both writing and reading whereas the 7200rpm model differs greatly in these two modes. It looks like the difference is due to the efficiency of deferred writing: the more effective and advanced algorithms, the more power is consumed by the HDD’s electronics. This is confirmed by the results of the Western Digital which has a small difference between the two modes, too.
The Hitachi 5K500.B, Toshiba and Fujitsu take top three places at sequential operations. Last three places are occupied by the two 3-platter models and the Seagate 7200.4.
We want to summarize the power consumption results of the Seagate 7200.4. This HDD has a higher spindle rotation speed than the others, which gives it an advantage. What is the tradeoff in terms of power consumption and heat dissipation? Comparing it with the Seagate 5400.6, the difference is not big: less than one fourth of a watt in idle mode and about 0.4 watts under load. The Seagate 7200.4 consumes about 0.4W more when idle and 0.6W more under load in comparison with the most economical 2-platter 500GB drives. (We mostly consider the results at reading because this Seagate behaves rather oddly at writing). And if compared with the rather voracious Western Digital or the 3-platter models, the Seagate 7200.4 is roughly as economical as them.