The MacBook Air with a solid state drive (SSD) was compared to the hard disk drive (HHD) version. While the SSD was better in some respects, it was worse in others, and the net gain was not substantial, according to ars technica on Tuesday.

The key finding was that the SSD drive performed better in random access tasks where the physical head movement in the standard HDD is a detriment. The SSD also performed better in read performance. However, in sequential access and in writing, the SSD did worse than the HDD.

Ars technica wrote: "The overall disk test scores arenit much different—29.37 on the HDD and 34.30 on the Air. But the SSD performs a fair amount worse than the HDD model when it comes to sequential read and write tests. The SSD was able to write sequentially between 14.67 and 13.86MB/sec, and sequentially read between 7.29 and 49.59MB/sec (the first and second numbers are differentiated by the size of the blocks being written). Comparatively, the HDD model sequentially writes between 31.35 and 33.33MB/sec, and reads between 6.32 and 32.74MB/sec for the same-sized blocks.

"But the random disk test is where the SSD model outpaces the HDD. The SSDis overall random read/write score was more than 40 percent higher than that of the HDD. While the HDD model was writing 256k blocks at 22.95MB/sec, the SSD Air was writing at 19.04MB/sec. But read speeds are significantly faster, and the HDD model read the 256k blocks at 14.37MB/sec while the SSD read at 47.61MB/sec."

The speed comparisons were made not only between the MacBook Air with an HDD and one with SSD, but also compared to a standard MacBook and MacBook Pro which makes the comparisons even more useful.

While the SSD may not be a slam dunk in speed advantage over the standard HDD, it still has the advantage of lower power consumption and a greater resistance to vibration and shock. Boot up time is also reduced somewhat.