Apple’s 128GB Solid State Drive (SSD)
The Apple 128GB (121GB) SSD is a relative bargain at a $100 upcharge from the hard drive, and if your needs are met by 121GB of storage, by all means it’s a good choice both on money and performance terms.
Falsely-stated capacity with Apple SSD
The Apple 128GB SSD offers 121.33GB of usable capacity . Which is false advertising.
To claim 5.7% more capacity than is actually there— imagine if a 16 ounce box of Cheerios contained 15.1 ounces of O’s— imagine the howls of protest and the lawsuits and government action. It would be on the evening news. Is this the new Apple “iMath”?
By comparison, the OWC Mercury Extreme Pro 240GB offers 240.06GB of usable capacity. By Apple’s standards, that makes the OWC offering a 256GB SSD, which would sure make a better sales pitch, but be just as untruthful. OWC’s 200GB Pro RE model would also be 256GB. The premise is absurd.
Presumably there is 128GB of flash memory inside the case of the Apple SSD, but it’s the usable capacity that must be advertised, not the implementation details, which can vary by technology, and do nothing more than confuse the consumer.
DiskTester was used for these results.
Shown below are sustained transfer speeds for the Apple 128/121GB SSD and the OWC Mercury Pro Extreme (the 200GB OWC Mercury Pro Extreme RE showed the same results).
The OWC SSD is about 30% faster than the Apple SSD, though this is unlikely to be noticed by the vast majority of users.
But note that coming SATA 6G SSDs will double the speed, so at that point (soon), Apple’s SSD will look quite slow.
The more interesting issue is how well the Apple SSD holds up over time; see the various severe duty tests for insight into this consideration.
See also SSD Performance With Random Data.
With large Photoshop files
With a large file in Photoshop exceeding available memory, disk speed is at a premium. Here the Apple SSD has outperformed the OWC SSD slightly (Photoshop CS5 12.0.2). When I tested with Photoshop CS5 12.0.1, the situation was reversed.
Why is the Apple SSD faster for this test? Because the data is random in nature (the test uses randomized image data inside the test image, not necessarily a common case for regular images). See SSD Performance With Random Data.