USB Port Power Surge

June 12, 2009 at 07:54:06
Specs: Windows XP
Hi folks, I have a WD external hard drive, brand new never dropped etc. As soon as I connect it on my lap top I get a "USB port power surge" warning. This doesn't happen when I connect it to other devices. However my LaCie external hard drive works fine on the lap top. The lap top is Dell Latitude D400. Thanks John

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June 12, 2009 at 08:27:02
External hard drives often require the USB port you plug them into can provide the max 500ma the standard USB specs provide for.
If you use a hub to connect a single external hard drive to the laptop, or especially if you connect two or more external hard drives to a hub that connects to a single port on the laptop, you are likely to have problems because the connection can't get enough current, and you may get error messages when you do.
If the external hard drive is 2.5", some come with (a) sufficient cable(s) to allow you to make two connections if one particular USB port can't provide enough current, some don't.

Also, some laptops can't actually provide the standard max 500ma from any USB port, and/or if you are plugging into a port in USB 2.0 controller PC Card (PCMCIA card) , it may not be able to supply the full 500ma to each port unless you plug in only one external hard drive and nothing else into it.

For more info, see response 3 in this:

and see response 1 in this starting at
"An external hard drive requires more current from the connection to the computer than most devices do."

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June 12, 2009 at 08:47:05
Thank you very much for the quick reply and advice

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