PowerBook G4 won't run USB-powered external HD

[rz]

I bought my wife a WD Passport drive - it's one of those small external, bus-powered USB2 hard drives. We went to hook it up, but it wouldn't work on her PowerBook G4 (15" model, 1.5 GHz, so it's got USB2 ports). We tried it in all the ports, but it just didn't work. So I tried it in my 12" iBook and it works just fine. So we tried the no-name external HD that I use, and it wouldn't work on her PowerBook either. The only way we could get it to work was to buy a powered hub, which kinda defeats the purpose of using it with a laptop.

Has anyone else noticed a problem like this with their PowerBook G4? She can use flash drives fine, and she can also use a smart-card reader that she needs for work. And yes, I made sure they were all unplugged before trying this.

[yeoman]

No problem here with PB 12in and bus powered external HD. Different enclosures and different 5400rpm drives all work OK w/o the nreed for powered hub.

[JEBB]

USB supplies 5V and Firewire 12V. For many drives 5V is marginally enough. You're always better off to get a Firewire drive when you want it to work by bus power.

I've never gotten a USB drive to work on any of my laptops. I have a PowerBook, an iBook and a ThinkPad.

[RAMd®d]

That's a not-uncommon problem with USB 2.0 2.5" HDs. Not all run off the bus power.

Some HDs come with a Y-connector that uses two USB ports to feed the enclosure, and some need the AC adapter as well as the USB connection.

It may be that your wife's PB just doesn't meet the demands of that particular HD. FW is far less problematic, but generally more expensive, and getting to be less common.

[yeoman]

Correction to my previous reply...I misunderstood your question. I do not have a USB2 dexternal drive. It's FW. Sorry.

[JoeH]

All Apple guarantees to be available on both USB 1.1 and 2.0 ports is 5 V and 500 mA of power. If your drive's power usage is within that, it should work. However, if it needs more than that to spin up, some ports may not be able to supply it, even temporarily.

[Jimmypoo]

I know the "on the go" drives from OWC work just fine from FW bus power, but I wouldn't sit there all day long and transfer gigabytes of data back and forth without having the little optional power supply.

I seem to recall, especially depending on the machine, too many people burning up FW ports - for whatever the reason, so when I CAN supply the power, and the drive will TAKE external power, I do.

Admittedly .... these 2GB USB thumb drives are beginning to make such toting of even little drives rather unnecessary except for you maniacs who have video on them!

[rz]

[quote RAMd®d]That's a not-uncommon problem with USB 2.0 2.5" HDs. Not all run off the bus power.

Some HDs come with a Y-connector that uses two USB ports to feed the enclosure, and some need the AC adapter as well as the USB connection.

It may be that your wife's PB just doesn't meet the demands of that particular HD. FW is far less problematic, but generally more expensive, and getting to be less common.
Hmm, my no-name drive came with one of those weird Y-connectors. I wondered what that was for. I'll have to give that a try with her PB. Although as I said, it's odd that my iBook seems to supply enough power to run either of them. In fact, I watched a whole movie off my external HD on a plane this weekend.

[Gareth]

I couldn't get a 2.5" USB drive to work bus-powered on my 15" PowerBook G4 1.25. Different machines will put slightly different amounts of power onto the bus.

I have one 2.5" Firewire enclosure that works on PowerBook G4's, but won't run bus-powered on my Pismo (Pismo has run every other 2.5" FW enclosure just fine). And my Cube's firewire bus seems overpowered and will run two FW enclosures bus-powered just fine (although I don't like to do that except in a pinch).

[Racer X]

FYI, the spec for FW is 12v 1.5 amps MAX per bus, and for USB 2 is 5 V 2.0 amps MAX per bus. So that is 18 watts for FW, and 10 watts for USB2.

That's why I use only FW bus-powered drives.