On 11/2/07, William Chops Westfield <westfw@mac.com> wrote:
>
> On Nov 1, 2007, at 4:36 PM, Xiaofan Chen wrote:
>
> > I read quite some website about USB things and often Mac is touted
> > to abide by the USB standard much better than Windows and even Linux.
> >
> > However it seems Mac is similar to other OS when it comes to
> > USB powered harddisk. They are supposed to be illegal USB device
>
> How come?  My mac seems to allow for some "startup time" before it
> complains of over-power.  The power issue with hard disks seems to
> be not so much their "average" power, but the power they draw when
> the disk is fist spinning up.

Those 2.5inch USB HDD which requires two USB cable to provide
the extra power (no external power) are in general illegal USB device.
Still all the major vendors are doing that. Please read the reply from
Pacer,  an USB expert and the author of USB Made Simple website.
http://forum.microchip.com/tm.aspx?m=276818

Western Digital Passport USB HDD in that post is one of the
examples.


Xiaofan
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