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Thread ID: 79089 2007-05-07 22:11:00 usb hdd not getting power mejobloggs (264) Press F1
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548127 2007-05-07 22:11:00 First time I have seen this happen, and can't figure it out.

My friend wanted some stuff transfered to their new pc, about 20gb.

I have a 2.5" usb hdd, which only plugs into usb, and doesn't have a wall plug, since it doesn't need much power.

So I took along my usb hdd, and plugged it in. It started beeping, indicating not enough power. I've never had that happen, but ok, so I plugged the second usb in, that is used to supply it with more power. Still beeping!

I can power it off a laptop running from a batteru with one usb plug, yet I couldn't power it off their new pc, what would be causing this??

Anything to do with it being a shuttle?
mejobloggs (264)
548128 2007-05-07 22:29:00 It could be the PSU since most Shuttles don't use 400W PSU's do they?

Or a PSU thats got enough watts in it.
Speedy Gonzales (78)
548129 2007-05-07 22:36:00 Try swapping the two usb plugs around.

I have a PC here with 2 front USB ports and if I plug in a 2.5" external USB HDD it only works with the USB plugs around one way.
If I try the other way it won't get power.
CYaBro (73)
548130 2007-05-07 22:57:00 Weird, I will give that a try when I can. Thanks. mejobloggs (264)
548131 2007-05-08 04:01:00 The USB system is a standard. Each port should supply up to 500 mA. Some manufacturers regard standards as "hints". :groan: They do care about cost of production. Laptops are sometimes a bit economical with the power to USB ports. I suppose some small desktops might also be a bit deficient. ;)

You should be able to use a powered hub to supply the full required current. It wouldn't be hard to make a special cable to insert external 5V. I think Silicon Chip magazine designed a kit a while ago. Jaycar have this double header USB cable (www.jaycar.co.nz/productView.asp?ID=WC7750&CATID=&keywords=usb+power&SPECIAL=&form=KEYWORD&ProdCodeOnly=&Keyword1=&Keyword2=&pageNumber=&priceMin=&priceMax=&SUBCATID=) to use the power from two USB ports, but if the computer is too mean with power it might not help. ;)
Graham L (2)
548132 2007-05-08 05:19:00 Never liked those for that reason.
I prefer the powered ones.

The PSUs watts may be enough but its the amps on the PSU. Stuff all and there isn't enough left for your drive.
pctek (84)
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