View Full Version : New PowerBook 15 won't talk to USB HardDrives

Michael Gyngell
Feb 17, 2005, 12:57 PM
Just received my new PowerBook 15/1.67. I've tried several different USB 2 bus powered hard drives without any success. The disks won't spin-up, and don't mount. System Profiler sees the USB interface of the drive but not the drive itself. The same disks worked fine on an iBook! Other USB devices, keyboard & mouse also work.

Has anyone else seen this behavior or is my PB broken (on arrival).

Sun Baked
Feb 17, 2005, 01:03 PM
Did you try both ports?

The specs say 500mA for both -- but people have found that in reality only one of the ports may provide full power.

Michael Gyngell
Feb 17, 2005, 01:11 PM
I tried both USB ports. Same behavior

Feb 17, 2005, 01:13 PM
Try differnet cables... I thought my firewire bus was shot when my ipod refused to spin up/mount turns out the cable just gave out... still gave power though just no data.

Michael Gyngell
Feb 17, 2005, 04:32 PM
I think that this is a known issue! There's a thread at discussions.info.apple.com (http://discussions.info.apple.com). It seems that the USB ports on the PB adhere very closely to the USB spec ... so if a device draws more than 500mA it won't work!!!!!

Feb 17, 2005, 05:40 PM
Please, break down and either do one or both of the following.

1) Purchase a Powered (by the wall) USB Hub. Attach Hub to PB, HD to Hub. The HD should now power up.

2) Purchase a power cable for the USB HD. Every USB powered HD should have the ability to use a power adapter. If not, try option 2.

3) There is no number 3.


Feb 17, 2005, 06:19 PM
USB doesn't give enough bus power for most hard disks. Get an A/C adaptor (should have come with it) or try a powered hub.