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General discussion

Slow data transfer speed, external to external

Feb 13, 2011 10:18AM PST

I have been storing all of my pictures and video files (~ 400MB) on a 1TB SimpleTech external HDD. I just bought a 2TB WD Elements external HDD to backup those files and to store additional movie files. Both are USB2.0, both have separate AC power. One is connected to a back port, and one to a front port. Both have been configured for max performance. Problem: when I start transfering files from the 1TB to the 2TB, the speed starts out at ~ 19MB/s max and slowly drops all the way down to < 1MB/s after a couple hours. Nothing else is running the background, and both drives are on a desktop in the open. Even if I only copy small chunks of data at a time, the transfer speed degrades. Is this normal (I think and hope not)? What is causing this and what can I do about it? I know I should be using an internal ASTA drive, but that's water under the bridge at this point. Thanks!

Discussion is locked

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Try rear ports only.
Feb 13, 2011 12:06PM PST

I find front ports to often error (silently) and the speed drop back to USB 1.0

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WAG, but...
Feb 14, 2011 12:01AM PST

Since both ports used are USB, the long and short of it, is that USB is not the fastest route to go. It will under these circumstances show its weakest. While speeds offered for USB use are under "ideal" conditions, these aren't meant for long by the end-user. Further, it maybe possible the ports differ as USB2.0 vs. USB 1.1, but that should be shown upon connection. regardless, this is an request to swap files and if anything else that int. to the system will have priority, so a simple backgrd. task could slow things down. Also, consider that a 1Tb and 2Tb HDs aren't small HDs and if you have huge data being transferred, and in the conditions explained here, it becomes more obvious the weakest of USB plus!!! what HD limits themselves. If one of these ext. HD is "green" they have a tendency to be slightly slower. If you like consider a USB3.0 card as future option. There could be other causes, but what I've explained may cover the topic.

tada -----Willy Happy

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Task Manager
Feb 18, 2011 11:07PM PST

Bring up Task Manager, find the application or task, and increase its priority.