Apple’s 2017 iMac 5K PCie flash storage versus other recent Macs

“How does the 2017 iMac 5K’s internal PCIe based flash storage speed compare to the previous iMac 5K and to the 2016 Retina MacBook Pro?” Rob Art Morgan asks for Bare Feats.

“With x4 Link Width and 8GT/s Link Speed, the 2017 iMac 5K’s PCIe based flash storage can now match the speed of the 2016 and 2017 Retina MacBook Pro’s flash storage,” Morgan writes. “What about the Fusion drive? We benchmarked the 2GB version. If transfer size is less that the free space of the ‘fused’ flash module, it can match the READ speed of the pure flash storage but the write speed was only one-third as fast.”

“Thunderbolt 3 transfer speeds matched the MacBook Pros as well,” Morgan writes. “Note that connecting two Thunderbolt 3 fast storage devices to separate Thunderbolt 3 ports and striping them does not double the transfer speed. That’s because they share the same bus.”

Read more, and see all of the benchmarks, in the full article here.

MacDailyNews Take: No major surprises.


    1. Well the retina iMac uses a 2.5″ HDD for fusion, not a 3.5″, so 3TB is best as it gets in that form factor. Now if you are arguing that the retina iMac should be thicker like the old iMacs to accommodate a larger drive, then yes Apple does like things thin.

  1. Stop buying into Fusion Drive concept. It made a difference/sense initially, when Apple was using 128GB SSD components. Then some time in 2013 I believe, Apple beancounters decided that 28GB SSD will be just as good, and increase their profits. Performance plummeted. Especially when paired with notebook size HDDs spinning at 5400 rpm. To check what you have in your Fusion Drive Mac, open System Information and look under Storage and SATA.

    I work in desktop support. Last year a unit with Fusion Drive, Late 2013 iMacs complained their computers were slow, even in simplest tasks — e-mail, browsing, word processing. And they were slow. NovaBench confirmed this with drive write speed scores of 40-46 MB/s. A 2011 iMac with 7200rpm HDD was doing “better” at 49 MB/s. The same 2011 iMac with HDD swapped for Crucial M4 SDD was scoring 225 MB/s. Heck, these Late 2013 iMacs with FD inside were scoring 216 MB/s when booted from external Thunderbolt 2 SDD!

    So we sent unit’s all six Late 2013 iMacs to authorized Apple repair shop and had their 2.5″, 1TB, 5400 rpm HDDs replaced with 2.5″ SDDs. When they came back, NovaBench scores were 377 MB/s !!! That’s 8-9 times better than with Fusion Drive configuration.

    Since this experiment we no more buy Fusion Drive Macs.

    Pure SSD speed boost is well worth the price difference. If you can’t afford Apple SDD price, especially the higher capacities, buy your iMac with Fusion Disk configuration, buy your own 2.5″ SDD, and take/send it all to authorized Apple repair shop to have them swap internal HDD for SDD of your choice. They will charge around $100 for labor, and it will not affect your warranty coverage. In a Mac mini you can follow iFixIt’s instructions and do the swap yourself, if you are handy with a screwdriver.

    Have fun!

    1. The top end model Fusion Drivrs they have 128 GB of flash storage…

      From Apple discussions forum

      “Hello community,

      I have found some extra details in Apple description : “The 1TB Fusion Drive pairs a 1TB hard drive with 32GB of fast SSD — enough to store important macOS files and applications to ensure fast startup, near instant wake from sleep, and quick application launching, with room left over for your most frequently used files and apps. The 2TB and 3TB Fusion Drives pair a larger hard drive with 128GB of fast SSD storage”

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