Not enough FireWire Power?

Hello,

on my new MPP17 C2D I noticed a dramatic change in the behaviourof the FireWire ports. It seems that less power is provided over both FireWire ports than on other/older MacBooks.

Example: I have an external WiebeTech FireWire hard drive that works without an external power supply on all older PowerBooks and even on my MacBook CD. It does not work on my brand new MBP17 C2D. It tries to power up the hard drive for 1 second or so, then stops, then tries again etc.

Is ist true that the FireWire specs on the MBP17 C2D have changed, or is someting wrong wit my MacBook?

Any help is greatly appreciated.

Leo

MBP17 C2D Mac OS X (10.4.8) 3GB/200GB

Posted on Nov 23, 2006 9:33 PM

18 replies

Apr 10, 2007 9:57 PM in response to Leo07

Hi there

I haven't had any trouble powering up my external FW400 drive (Mercury On-The-Go with 80GB/5400rpm Hitachi Travelstar HTS541080G9AT00) from my MacBook Pro's FW400 port.

What I have had a problem with, however, is that the MacBook Pro FW400 port doesn't seem to provide the right voltage or current to power a Griffin iFire (to which my Apple Pro speakers, ex PM G4, are connected). The FW400 ports in all my previous PowerBooks (G3 Pismo, G4 Ti (667MHz & 1.0GHz) and G4 Al (1.67Ghz DL SuperDrive) have all had no difficulty in powering the iFire, and it seems I am not alone in having this problem — see #28 at <http://www.atpm.com/10.02/ifire.shtml>. I've ended up connecting the iFire directly to an old iPod Firewire power adapter.

I'm not sure what the difference is, but there seems to have been some change to the power out specs for the FW400 port since the last of the PowerBooks — Does anyone know what has changed?

MacBook Pro 17" 2.33GHZ Mac OS X (10.4.9) 2GB RAM

Peter Lin

Level 2

185 points

Apr 11, 2007 10:03 AM in response to Leo07

I'm experiencing the same problem. I have a Macally PHR-250CC 2.5" enclosure with a Western Digital drive in it. Power over USB has never worked, but I was able to power the drive using Firewire ports on every Mac I've owned except for my new 15-inch MBP C2D 2.33Ghz with or without the power adapter attached. Works fine on an iMac C2D, Intel Mac mini, MacBook CD, and even a 7 year old Pismo Powerbook.

Has anyone contacted AppleCare about this? I'm curious if they will acknowledge that it's even a problem.

15-inch MacBook Pro C2D 2.33GHz Mac OS X (10.4.9)

Apr 23, 2007 7:16 AM in response to Peter Lin

No problems here with a Wiebetech Toughtech Mini enclosure containing a Seagate 160GB 5400rpm SATA 2.5" drive. On a 15" MBP C2D.

Spins up and works fine on both FW400 and 800. (Although, the FW800 connection doesn't move data any quicker than the FW400, so lesson learned - don't bother paying extra for FW800 on a single-drive notebook enclosure.)

(This enclosure is also sold by quite a few other retailers, just branded differently).

My concern is that I want to get a Lacie Little Big Disk 320GB, which is two notebook drives in one enclosure, as a striped RAID. Anyone tried one of these on an MBP? It's supposed to work over bus power, which is kind of the whole point.

The drive specs say they need about 1 amp each to spin up. So two drives in the LaCie will need 2A. But Apple's spec seems to indicate that the MBP can only put out a max of 1.5A over firewire.

If the Little Big Disk won't work over bus power, I'm saving $200 and getting a 3.5"-based drive, and putting up with the external PSU.

If you're having trouble, can you be specific what drive you're trying to bus-power?

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Not enough FireWire Power?