USB transfer rates

Discussion in 'Mac Accessories' started by theLastBeatle, Oct 30, 2009.

  1. theLastBeatle macrumors member

    Oct 25, 2007
    Hey everybody,

    I have a "My book Pro" 250 GB external hard drive spinning at 7200 rpm. This thing is dog slow. It takes about 5 to 10 seconds to copy about 2 megabytes.

    I have another drive that copies about 160 megabytes in about 5 seconds.

    I called Western Digital (the maker of the "My Book Pro") and they said that USB 2.0 transfer rates are about 2 MB a second! That is not true but he insisted.

    My question to you all is how can i win this argument with them? Do you know a formula that would give me real world numbers. In other words how to translate 480 megabits (the USB 2.0 transfer spec) into megabytes? Ive searched the net and cant find anything.

    Its messed up cause both drives have basically the same specs. Ive even tried reformatting to every possibility, ive switched cables from the fast drive to the slow drive. Nothings working. Im gonna call WD back tomorrow but i wanted a way to talk about what could honestly be expected from USB 2.0. I just cant believe that USB 2.0 tops out at 2MB a second. And to top it all off, todays call ended up with me getting disconnected so i called back and guess what, they were closed...that guys a DOUCHE.

    anyway thanks for the help in advance.

    PS I really cant put my faith into Western Digital after this. Are there drives that are geared more towards professionals seeking performance and reliability?
  2. Big-TDI-Guy macrumors 68030


    Jan 11, 2007
    8 bits to a byte. So divide by 8.

    So "top speed" for USB 2.0 is 60MB a second. But there are other factors, 480Mb data rate isn't sustained.

    Most hard drives these days (in the 7200rpm range) have sustained data rates at least double of USBs peak. (1.5Gb or 3.0Gb SATA interface outpaces the read/write capability of the drive itself)

    That said, 2MB data rate is in USB 1.0 territory, and I wouldn't be happy about it.
  3. spinnerlys Guest


    Sep 7, 2008
    forlod bygningen

    8 bits = 1 byte, so 480 Mbit/s are 60 MByte/s.

    Also USB 1 has a transfer rate of 12 Mbit/s = 1.5 MByte/s.

    And the WD MyBook should have definitely better USB transfer speeds.

    Can you return it to where you bought it?

    And speaking of WD's drives, I have a dozen My Studio HDDs at work, and they work quite good and take a bump or two with honour. We also had one LaCie once (a company I swore by then), and that HDD failed within 5 months.
  4. theLastBeatle thread starter macrumors member

    Oct 25, 2007
    spinnerlys -
    I guess its just my drive. I cant really keep the faith after this especially since the representative said the drive was performing within spec. But im glad your having great success with WD. And thank you for your input and formula.

    Big-TDI-Guy -
    Thanks to you as well.

    I appreciate both of your time.
  5. spinnerlys Guest


    Sep 7, 2008
    forlod bygningen
    Then tell the representative he can Fox himself.

    WD advertises the HDD working within the specs of USB 2.0, which shouldn't mean working at the bare minimum speed and slightly above USB 1.1.

    You're a dissatisfied customer and you have the right to complain. Do you know of any other users of this drive model of yours and if they could confirm the slow write speed?

    There are USB flash drives out there that are faster.
  6. theLastBeatle thread starter macrumors member

    Oct 25, 2007

    I dont know anyone with the My Book Pro but i searched online and it seems there have been some issues with speed. Haven't found a fix that works though. Im going to call WD tomorrow (or monday) and hopefully make some progress.

Share This Page