The Fusion Drive wrote data from the Pegasus at around 270 MBps and dropped to 70 MBps. Our folder copy tests showed a similar pattern. The 1TB hard drive performed almost identically to its read times, about 90 MBps, slowing a bit to 85 MBps as the test approached 200GB of data copied.Ĭopy files from external storage to internal storage Macworld Lab testing by James Galbraith and Albert Filice. That was a bit faster than the 120GB SSD, which averaged around 270 MBps until it filled up. The Fusion Drive started out at 284 MBps and then dropped to about 80 MBps after the threshold of 100GB of data copied was crossed. The 1TB hard drive started out at around 90 MBps and remained consistent, finishing the test at a little more than 83 MBps.Ĭopy files from internal storage to external storage Macworld Lab testing by James Galbraith and Albert Filice.Ĭopying the files in the opposite direction-from the Pegasus to the Fusion Drive, or SSD, or hard drive-showed a similar (though slower, overall) pattern. When we changed the configuration to test copying files from the SSD to the Pegasus, we also saw speeds of 470 MBps, but the test stopped once 100GB of data copied, hitting the SSD’s capacity limits. Copying the files from the Fusion Drive to the Pegasus cooked along around 470 MBps until approximately 100GB worth of files had been copied, at which point the speed dropped down to about 80 MBps.

Imac fusion drive vs ssd speed test