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I bought a Seagate Expansion portable disk (1 TB).

I am using a Dell Inspiron 15R (5521) laptop which has 2 usb 3.0 ports. But when I transfer files to my above mentioned portable drive I do not get a transfer speed of more than 35 MB/s. Sometimes the speed is slower than that. What is the issue here, and how do I fix it?

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Are you sure your using the USB 3.0 port instead of the USB 2.0 port? Furthermore what makes you think 35MB/sec isn't fast compared to the speeds of a USB 2.0 device it would actually be several times faster. In addition because its a mechanical HDD there are speed limitations connected to that fact. –  Ramhound Aug 21 '13 at 11:11

2 Answers 2

The common causes are:

  • cable
  • driver
  • USB2 port

So make sure it's a USB3 cable from end to end and try a different one in case it's just a bad cable. Then update the drivers to the latest for your USB3 hardware. Finally try both USB3 ports on your laptop (looks like they are the two on the left furthest away from the audio jack).

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The cable is usb 3.0, and it is brand new. Even if I try to transfer files to a flash drive using usb 3.0 the speed is very low –  DesirePRG Aug 21 '13 at 11:40

Intel make only one driver for usb3 with Windows 8. This driver downgrades the transfer speeds to the lowest common denominator within the system. In other words, if it senses any usb2 device or a faulty/substandard usb3 device, the fastest your usb3 system will transfer data at will be at a self determined (Intel usb3 driver) speed.
So, try removing all other usb devices and see what speeds you get! I'll bet it takes off like a rocket (on the assumption your new portable drive is 100% ok).
Finally, the Intel usb3 driver seems to be extra sensitive so don't expect data transfer rates to be at the theoretic/quoted possible speeds. That's a pipe dream but never the less, will be much faster than usb2.

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