How many usb portable hard drives can be connected to a PC at the same time?

Discussion in 'Peripherals' started by peter236, Jul 6, 2012.

  1. peter236

    peter236 Junior Member

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    Suppose the PC motherboard has a couple of usb ports.

    How many usb portable hard drives can be connected to a PC at the same time? If I connect 2 external portable drives to 2 different usb ports, will that be okay? I presume one drive connected to each usb port should be alright. I would like to copy files from one drive to another.
     
    #1 peter236, Jul 6, 2012
    Last edited: Jul 6, 2012
  2. Soundmanred

    Soundmanred Lifer

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    I've had 9 at one time, so 2 shouldn't be a problem.
     
  3. richaron

    richaron Senior member

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  4. imagoon

    imagoon Diamond Member

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    127 drives per usb host port. On some system boards one host port might provide 2-6 usb ports on the back of the system.
     
  5. boochi

    boochi Senior member

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    If they are powered over USB, you may only be able to run one or two.
     
  6. peter236

    peter236 Junior Member

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    My 2 external portable drives do not have their own power adapter. But I just connect them to different usb ports at the back of the PC. I am not using any usb hubs or any chaining at all.
     
  7. DesiPower

    DesiPower Lifer

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    yeah, so how exactly does that work? is it dependent on the controller? like one controller can only supply 2A of current or something like that? does that capacity/amp depend on the controller type/make? or is it the number of port? each port can provide 1A....
     
  8. imagoon

    imagoon Diamond Member

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    Spec (1.0 / 2.0) provides .5A to each port. Depending on how the ports are divided up, you can have .5A at each or some smaller amount. Some older system boards used a root hub to make one controller give you 2-6 ports but with only .25A or .1A available. Others used more power to give you .5A at all ports. It is dependent on board design.
     
  9. Anteaus

    Anteaus Platinum Member

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    The practical limit is 26, unless you somehow hack windows to allow alphanumeric drive assignments. The physical limit is higher, but that will require swapping assignments as needed. However, you might be able to map drives to folders instead of drive letters.

    OP, as long as they are self powered drives you won't have any problems. Also, multiple USB ports might belong to the same controller which mean shared bandwidth, so if you want to maximize transfer speeds make sure they are on seperate controllers. In the event you have only one USB 3.0 controller, it would be acceptable to use both drives on the one controller. .02
     
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