Solid State Disks are power guzzlers

Besides performance advantages of SSDs, one thing manufacturers like to make claims about is their supposedly superior power consumption over traditional mobile hard disks.  Well, just like how we recently reported about unexpectedly high failure rates of SSDs, it turns out that the power consumption of the average SSD not only fails to improve upon 5400RPM hard disks, but also gobbles more energy than even a 7200rpm 2.5" drive!  At least that’s what Tom’s hardware has found in its extensive set of benchmarks recently carried out.

In the benchmark, Tom’s hardware compared 4 SSDs against a 200GB Hitachi 7200 2.5" hard disk that were handy in its test lab, all using a Dell Latitude D630 laptop.  What they found was very surprising.  While all the SSDs blew away the HDD for read performance and seek time, the hard disk gave the longest run time of just over 7 hours in this test machine.  Two of the SSDs, the Crucial and Mtron Flash 32GB SSDs, consumed so much power that they both reduced the battery life by about an hour!  The tests were run using Mobilemark 07, which keeps the laptop and drive busy by simulating usage.

While in theory hard disks are rated with higher power consumption figures than SSDs, what Tom’s hard ware found is that hard disks only consume their maximum power when randomly seeking, somewhere between 2 and 4 watts while randomly seeking.  Their power consumption is very low when idle or reading sequentially, at between 0.5 and 1.3 watts.  However, they found that SSDs on the other hand consume their maximum power when in use, not just when "seeking".

One other thing Tom’s hardware found is that the power consumption of 1.8" SSDs is no lower than 2.5" SSDs, yet, 1.8" hard disks consume significantly less power (maximum 2 watts) than 2.5" hard disks.  So those who plan getting an SSD instead of a hard disk for an ultra-compact laptop may end up with a significantly reduced runtime.  Also, those who replace their existing laptop hard disk with an SSD, primarily for better battery life, will also experience disappointment.

So it looks like after all this time, at least none of these SSD manufacturers have actually benchmarked their hard disk against traditional hard disks in real world tests.  As Tom’s hardware said, surely they would have noticed the extra power consumption, particularly when all four SSDs benchmarked could not even beat the high end 7200rpm 2.5" Hitachi drive, never mind a 5400rpm 2.5" drive.