Usb 3.0 mbp

Discussion in 'MacBook Pro' started by molson2k, Jun 20, 2012.

  1. molson2k macrumors member

    Oct 13, 2007
    Hi, I recently purchased the base 13-inch MacBook Pro with USB 3.0 support.

    I, in turn then upgraded my external hard drive enclosure to USB 3.0 (this particular model

    However, I'm still getting roughly USB 2.0 speeds (30-35 MB/s). I was expecting data transfers to be at least somewhere in the 100 MB/s range.

    The hard drive is 5400 rpm/SATA/60 gb from my original white MacBook five years ago. Could the USB 2.0-ish speeds be related to me using such an aged hard drive?
  2. killmoms macrumors 68040


    Jun 23, 2003
    Washington, DC
    Very few hard drives can ever hit 100MB/s sustained (pretty much only modern, high capacity, and high rotation speed ones), and certainly not 5400RPM laptop drives from five years ago. So yes, you are being bandwidth limited by the drive. If you put an SSD in that enclosure, you'd see much higher speeds.
  3. Southernboyj macrumors 68000


    Mar 8, 2012
    Mobile, AL
    As the guy above me stated, the drive is definitely your bottleneck.
  4. Ozy macrumors regular


    Aug 8, 2006
    Goodyear, AZ
    I just moved my 500gb 2.5" 7200rpm Seagate momentus drive from the old FW800 enclosure to a USB3 $14 enclosure. I formatted it fresh to use on my rMBP as a TimeMachine backup. I was able to sustain 125MB/sec to it during good portions of the backup. I am very happy with that throughput via USB3.
  5. molson2k thread starter macrumors member

    Oct 13, 2007
    Thanks for this reference. I'll be sure to pick up a 7200 rpm drive now!
  6. yg17 macrumors G5


    Aug 1, 2004
    St. Louis, MO
    Stupid question, but are you using a USB 3.0 cable?
  7. SDAVE macrumors 68040


    Jun 16, 2007
    Also to add, USB3.0 is limited to 5Gbps (even less, with overhead) and modern SSDs support SATA speeds upto 6Gbps (much less overhead than USB3.0) so in other words, even the USB3.0 protocol will limit the speeds of your SSD. Hard Drives will be fine, though.
  8. molson2k thread starter macrumors member

    Oct 13, 2007
    Yes, I am using a USB 3.0 cable.

    Also, I recognize that USB 3.0 will never ever reach 5 Gbps. I was expecting a maximum throughput of 2.5 Gbps (312 MB/s) with overhead and at least a minimum transfer rate of 100 MB/s.
  9. jcpb macrumors 6502a

    Jun 5, 2012
    You're using a SATA1 hard drive in a SATA3-USB3 enclosure. You are bottlenecked directly by the hard drive here.

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