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General discussion

Problems with bus-powered USB Ext. HD's?

May 16, 2009 8:46AM PDT

Looking to get a WD Passport to take my music and such with me while travelling (without the hassle of the power adapter for the external HD), but it looks like some people have noted issues with transfering large files/directories. Is this just rumor or is it really an issue? Most of the use would be backing up My Docs, music, and video folders, so fairly large directories.

Discussion is locked

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Some machines, not all.
May 16, 2009 8:59AM PDT

USB power is not that reliable. While those cables that connect to two USB ports seem to fair better you still see your occasional failure on some machines.

Will yours work? No one can answer.
Bob

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I use Y-cable
May 16, 2009 5:19PM PDT

I used ext HDD USB based, and single cable to power one is a high risk, if your USB port drops power output, it's going to be very unstable which I learnt the hard way, thus have been using the Y-based one which gives me more peace. Good thing is my casing has an additional direct power as well which I used it as even with Y-cable, if your port is cranky, ain't going to help without additional external power.

I did transfer large ISO files of 2GB straight off from my laptop to the disk, stable but it's slow, even though both are NTFS.

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I've found . . .
May 16, 2009 10:28PM PDT

when I plug in my external USB drive, and the laptop is on batteries, I have problems. When the laptop is plugged into the charger, no problems.

Laptops running on batteries are very frugal on what is plugged into the USB ports.

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Oh definitely I wouldn't use bus power when running on batt
May 17, 2009 1:05AM PDT

But as you mention, I figured that as long as its running on AC power, it should be fine.