Is there a way to speed up USB 2.0?

Discussion in 'Mac Accessories' started by DobaKung, Oct 6, 2013.

  1. DobaKung macrumors newbie

    DobaKung

    Joined:
    Oct 13, 2011
    Location:
    Thailand
    #1
    Hi,

    I'm wondering that the USB 2.0 have a transfer speed at 480 MB/s but why mine can only transfers at around 30-40 MB/s? The devices I'm using are supported the USB 2.0 (High speed) and one even support 3.0! Is there anything wrong with my Mac or is there a way to speed it up?

    Thanks in advances,
    Nathan.

    PS. I'm using a late 2008 Aluminum Unibody MacBook model.
     
  2. Puonti macrumors 6502a

    Joined:
    Mar 14, 2011
    #2
    USB 2.0's theoretical maximum transfer speed is 480 megabits per second (Mbit/s), which translates to 60 megabytes per second (MB/s). It sounds like you're seeing real world performance on par with the standard.
     
  3. DobaKung thread starter macrumors newbie

    DobaKung

    Joined:
    Oct 13, 2011
    Location:
    Thailand
    #3
    So, this is the fastest speed I can get?
     
  4. Giuly macrumors 68040

    Giuly

    #4
    Unless you use something else than USB (in your case Gigabit Ethernet), yes.
     
  5. Julien macrumors G3

    Julien

    Joined:
    Jun 30, 2007
    Location:
    Atlanta
    #5
    Also just to be sure you aren't confusing MB with Mb. 40MB is 320Mb and would be an excellent real world speed for a USB 2.0 connection.
     
  6. thedeske macrumors 6502a

    Joined:
    Feb 17, 2013
    #6
    That's about right.
     
  7. DobaKung thread starter macrumors newbie

    DobaKung

    Joined:
    Oct 13, 2011
    Location:
    Thailand
    #7
    A little confusing...

    MB = Megabytes
    Mb = Megabits

    Am I right?
     
  8. Julien macrumors G3

    Julien

    Joined:
    Jun 30, 2007
    Location:
    Atlanta
    #8
    Yes, but in your OP you said USB 2.0 speed is 480MBps but it's 60MBps (480Mbps) and you were getting 30-40MBps which is 240Mbps- 320Mbps. If you measured 30-40MBps then you are getting very good real world USB 2.0 speed.
     
  9. Menel macrumors 603

    Menel

    Joined:
    Aug 4, 2011
    Location:
    ATL
    #9
    Except when MB = Mebibytes

    ----------

    lower case b = bits. Upper case B is Bytes. 8 bits in a byte.

    USB2 spec is 480mbps.

    Its most likely going to use 8b/10b encoding, so you lose 20% right away, down to 384mbps.

    384mbps is 45.7 MB/s max.
     
  10. takeshi74 macrumors 601

    Joined:
    Feb 9, 2011
    #10
    It doesn't matter if the device is USB 3. A chain is only as strong as its weakest link. If your Mac is USB 2 then that's the best you'll get. You also need to consider that there is overhead so you won't get the theoretical max USB 2 speed to begin with.

    Doesn't sound like anything is wrong unless you're getting 30-40Mb. As stated above, 30-40MB is great for USB 2.
     

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