Samsung Evo 850 2TB USB 3.0 Speed Normal?

Discussion in 'iMac' started by orangefridge, Oct 6, 2017.

  1. orangefridge macrumors newbie

    Mar 1, 2013
    After eventually talking myself out of putting my Samsung Evo 850 inside my laste 2015 i7 iMac, I purchased a USB 3.0 external enclosure (inatek) as many people recommended it would be optimum speed.

    I was under the impression I would be getting much faster Read / Write speeds than I'm getting.
    Am I missing something? Just formatted to Mac OS Extended (Journaled)

    Do I need to reformat it different? Firmware updates? (Can't find for this model)
    If this is my maximum speed I may as well stick to my Lacie.


    Attached Files:

  2. satinsilverem2 macrumors 6502a


    Nov 12, 2013
    Richmond, VA
    Thats pretty low im using a Satechi enclosure with that same drive and am getting 500/480 read/ writes so I would say that your enclosure is limiting you. what is the enclosure?
  3. Fishrrman macrumors P6


    Feb 20, 2009
  4. nikolajlr macrumors member

    May 11, 2011
    Dug out some old tests I did back in 2014 - beware that the Disk Speed Test dials seem to have had another scale than the current version, so only look at the numbers.

    This is what I got on my iMac 27 2011 using a CalDigit Thunderbolt Station with USB3 with a Samsung 840 EVO 250 GB in a StarTech S2510BPU33 USB 3.0 chassis with UASP:
    DiskSpeedTest S2510BPU33 UASP.png
    With a Delock chassis without UASP, same SSD:

    DiskSpeedTest Delock 42475 no UASP.png

    And Thunderbolt 1: Samsung EVO 840 500 GB (note: it is by design faster than the 250 GB version above) in external Buffalo MiniStation Thunderbolt 1 chassis (came with HD I swapped out) and with TRIM enabled:
    DiskSpeedTest TB MiniStation 500 GB Samsung 840 EVO TRIM.png
    So it seems like you should be able to get better performance than you currently see.
  5. Fishrrman macrumors P6


    Feb 20, 2009
    I believe some speed is lost (via USB3) when "going through" an external dock (like the CalDigit, etc.)

    Connect the USB3 SSD -directly to- one of the Mac's USB3 ports, and test it again.

    I have a 2012 Mac Mini which I boot and run using SSD's mounted in external USB3 docking stations. I get reads of 431mbps from both drives.

    You should see 430mbps at least...

Share This Page

5 October 6, 2017