What is USB2.0 speed?

[edong]

I'm trying to move some 300GB of files from 1TB WD to 2TB WD externals. One PC with AMD Quad-Core has transfer speed of 10MBps while the other PC with Pentium i7 has transfer speed of 15-20MBps. I thought USB2 has speed of 40-60MBps. Both have Windows 7. Will that depend on the PC configuration? I doubt these externals will only have that speed although I could not find the specs on the boxes.

[El Heggunte]

USB works "one-way at at a time", NOT "two-ways at the same time". So, the maximum transfer speed to an external HDD should be around 30MBps. In the "real world", it floats between 20MBps and 25MBps most times. A value as low as 10MBps does smell "fishy" though.

[Cornucopia]

No, not too surprising if you are talking about sustained transfer, the probable overhead of other background processes, and possible competing usb traffic.

Scott

[Hoser Rob]

10 Mb/s sounds a wee bit low to me too. What type of files are they? Large files like video ones will move faster than a much larger number of smaller ones.

One factor that I kind of hate to mention is that both processors may be quad core but that doesn't mean they have equal speed.

Also, whether you get the maximum theoretical usb speed depends a lot on your drives.

Cornucopia's comment about system overhead is right on. Under windows 7 I would rarely get much more than 25 Mb/s. In linux I routinely get over 40 Mb/s with the same drives.

[The_Doman]

Often you can improve/maximize the write speed by enabling the write caching option on the USB drive.
I always do this with my external USB drives, makes quite a lot of difference.

Windows 7 Forums: How to Enable or Disable Write-Caching for a Storage Device in Windows 7

[Hoser Rob]

... [insert emoticon for slapping the side of my head] ...

How in the hell did I forget that?

[El Heggunte]

Me too had forgotten the damn feature

But here goes the appropriate emoticon for the occasion:

[mike20021969]

You could see if TeraCopy improves things: http://codesector.com/teracopy

From the TeraCopy website:

One of the most common complaints about newer versions of Windows is the slow copying speed, especially when transferring lots of files over the network. If you want to speed up your copying or if you regularly transfer large amounts of data and have to stop the process to perform some other disk-intensive task, this program may be just what you need.

[edong]

Thanks, guys. It's mostly Happauge HiDef captured files(.ts) with 300-700MB in sizes . I'll try the suggestions next time I do this. For now, it's done after maybe six (6) hours.

I have noticed that transfer speed is faster if I do it like 1-2GB(total file sizes) at a time though. Seems it's choking when dealing with large volumes. Just too lazy to go that route.