Hard Disk Drive
Our MacBook shipped with the Toshiba MK1653GSX SATA-II 160GB drive. MacBook 2.4 GHz machines with 250 GB also ship with Toshiba HDDs. These drives have some of the highest areal densities per platter (254 gigabits per square inch). The 160 GB drive is a single platter design with two data heads. Average seek time is 12 ms with a track-to-track of 2 ms to a maximum of 22 ms seek. Seeks require 2.2 watts, read/write eats up 1.9 watts, while idle power consumption is 0.85 watts. MTTF is a disappointing 300,000 hours.
We also tested a MacBook that shipped with a Fujitsu MHZ2160BH SATA-II 160 GB drive. Track to track time is a faster at 1.5 ms and idle power consumption is better at 0.6 watts. Read/write is slightly worse at 2.1 watts. Seek power consumption is not reported. MTBF is also a disappointing 300,000 hours.
The unibody MacBook Pro ships with a different 5,400 rpm drive. We’ve seen MBP’s shipped with Hitachi Travelstar 5K320 drives (HTS543232L9SA02). While this specific model is not listed in Hitachi’s product documentation, the “SA0” designation typically refers to SATA 1.5 Gb/s designs as opposed to SATA 3.0Gb/s. This only makes a difference when transferring data from the cache to the host as 5,400 rpm notebook drives are unable to saturate a SATA 1.5 Gb/s connection. In theory, SATA 1.5 Gb/s connections require less power than SATA 3 Gb/s connections. Average seek time is also 12 ms, but the track-to-track time of 1 ms and a maximum full stroke of 20 ms is slightly faster. Seeks require 2.2 W, read/write is superior at 1.8 W, and active idle consumption is 0.8W. MTBF is not disclosed.
In general, these are run-of-the-mill notebook HDDs and we recommend upgrading to aftermarket HDDs. Time Machine makes it extremely straightforward to migrate your computer from one HDD to another (provided that you have an external drive). One good choice is the Seagate Momentus 7200.4. Not only is this a 7,200 rpm drive for added performance, but power consumption is improved to 1.554 W for seeks and 0.67 W at idle. MTBF is 500,000 hours. The Seagate drive offers a 5 year warranty as opposed to the 3 year of the Toshiba, Fujitsu or Hitachi drives that ship with the MacBook and MacBook Pro.
Solid State Storage
For our setup, we elected to go with solid state drives. SSDs are available in two formats: SLC and MLC. SLC is more expensive but offers added reliability and performance. MLC allows higher density memory chips to be produced, resulting in higher capacity drives at relatively affordable prices. Many of the early budget MLC solid state drives have been reported to have poor performance with small files (“stuttering”). The newer MLC drives that ship from Apple directly (manufactured by Samsung), the Intel X-25M, and the OCZ Vertex SSD line are all expected to have good performance because they use a different memory controller.
We elected to go with the OCZ SATA-II 64 GB SSD. Based upon Samsung’s SLC SSD technology, the OCZ solid state drive features a flagship 2,000,000 hours MTBF. In addition to the added performance and reliability that solid state drives can offer, the OCZ drive also adds considerable performance benefits over the standard 5,400 rpm hard drives. Power consumption during read/writes is just 0.5 W and 0.35 W with an idle of 0.2 W.The Intel X-25E is expected to offer the same level of reliability as the OCZ drive (2M hours MTBF) with even greater performance.
The enthusiast-priced Vertex SSD drives from OCZ have an MTBF of 1,500,000 hours and use a new memory controller which is supposed to prevent the stuttering that has plagued the other budget drives. The Intel X-25M has an MTBF of 1,200,000 hours. The Samsung MLC drives available in 128 GB capacities shipping in current MacBooks have an MTBF of 1,000,000 hours.
Going to SSD halved our boot times to about 25 seconds as compared to 56 seconds off the 5,400 rpm drive. Interestingly, the time it took to write a 2GB file was nearly equivalent to the boot time:
Time to Write 2GB File (1k blocks)
Factory installed HDD: 50.577 seconds (42.46MB/sec):
OCZ SATA-II SSD: 25.076 seconds (85.63MB/sec)
Time to Read 2GB File (1k blocks)
Factory default HDD: 49.915 seconds (43.03MB/sec)
OCZ SATA-II SSD: 18.935 seconds (113.41 MB/sec)
|Stock HDD (5400 rpm)||OCZ SATA-II SSD|
|Write 2GB File (1k blocks)||42.46 MB/sec||85.63 MB/sec|
|Read 2GB File (1k blocks)||43.03 MB/sec||113.41 MB/sec|
|Uncached Write (4k blocks)||62.07 MB/sec||85.56 MB/sec|
|Uncached Write (256k blocks)||46.28 MB/sec||77.91 MB/sec|
|Uncached Read (4k blocks)||19.76 MB/sec||17.5 MB/sec|
|Uncached Read (266k blocks)||55.82 MB/sec||95.34 MB/sec|
|Uncached Write (4k blocks)||1.26 MB/sec||5.2 MB/sec|
|Uncached Write (256k blocks)||26.58 MB/sec||69.41 MB/sec|
|Uncached Read (4k blocks)||0.46 MB/sec||10.58 MB/sec|
|Uncached Read (266k blocks)||21.01 MB/sec||93.82 MB/sec|