[sk8008]

Hello All,

I am about to purchase a Lacie P3 250gb external, but cannot find a firewire version in stock until the end of February in the UK according to Lacie. I plan to use the drive for backups and to clone my G5.

Out of interset I would like opinions regarding whether I should wait for the FW version or if a USB2 version will be adequate.

I have read about the FW having a better constant data transfer but will this make a real difference for backups?

Cheers

sk8008

[DMBand0026]

USB 2.0 is faster than FireWire 400, but not 800. If the drive you're looking to buy will have the 800 option I'd say go with that, but if it's just going to be 400 USB 2.0 will be just fine. And since it is just for backups I don't think you'll be very concerned with consistent data transfer.

[octavist13]

Originally Posted by DMBand0026 USB 2.0 is faster than FireWire 400, but not 800. If the drive you're looking to buy will have the 800 option I'd say go with that, but if it's just going to be 400 USB 2.0 will be just fine. And since it is just for backups I don't think you'll be very concerned with consistent data transfer.

"Ditto"

[Jay]

I personally prefer firewire 400 over USB 2.0 but I assume you are going to be backing up overnight so it really doesn't matter, going either way won't change the times all that much.

You might want to consider building your own drive which I did. Mine is a 200 GB Seagate with a MacAlley enclosure from OWC and it was only $215 with tax and shipping back in Sept.

I'll see if I can run a test on my set up to see if there is any differences tonight but I'll be limited to the speed of the laptop drive more than likely.

[curiousuburb]

Originally Posted by DMBand0026 USB 2.0 is faster than FireWire 400, but not 800.

um... USB 2.0 in burst mode may be faster than FW400, but in sustained use FW is faster.

Plus... with a 6 pin Firewire cable, you could run some drives without their power adapter via bus power. USB tops out at 500mA per port, and the portable 2.5" USB 2.0 drive I just set up for a client required 550mA for its 60GB Fujitsu drive, so the USB 2.0 actually needed two USB ports on his iBook for power.

Many chassis models also come in "combo" with both USB 2.0 and FW400 ports for only $10 more.

FireWire is superior, IMO. Might be more 'future proof'. YMMV.

[Jay]

Now for the results of an almost scientific study.

Test Platform
Powerbook G4 12" 1 GHz 768 MB
External HD: Seagate 7200.7 200 GB 8 MB buffer mounted in MacAlley case.

The Test: Copy of my user folder. Total size 27.01 GB, contains 20 GB iTunes library, 5 GB DV footage, 2 GB misc documents and pictures.

Now for the Scores

2nd Place USB 2.0 with a time of 32:25 with average sustained rate of 13.88 MB/s

1st Place Firewire 400 with a time of 27:12 averaging a sustained rate of 16.54 MB/s

So there is lead with Firewire, whether you consider it worth the wait is up to you but if you are backing up 250 GB there will be a sizable time difference. I'm still in the do-it yourself camp, it took me 5 min to assemble it, with 4 screws and connecting 2 cables, and I saved probably $40.

[chucker]

2nd Place USB 2.0 with a time of 32:25 with average sustained rate of 13.88 MB/s 1st Place Firewire 400 with a time of 27:12 averaging a sustained rate of 16.54 MB/s

Interestingly, neither even comes close to their theoretical rates (USB 2: 480 MBit/s = 60 MB/s; FW 400: 400 MBit/s = 50 MB/s).

[Luca]

Point is, there will be very little difference between USB 2.0 and Firewire. And unless you're using a special enclosure designed to be bus powered, it'll require AC power. The only bus-powered hard drive enclosures you can get are 2.5" ones, and certain low-power 3.5" ones that are only bus powered if you install a 5400 RPM hard drive. The LaCie is not one of those, so regardless of which you choose, you'll have to use AC power.

I've noticed that USB 2.0 enclosures seem to cost less than Firewire. In that case I'd just go for the cheaper one.

[Jay]

Originally Posted by Luca Point is, there will be very little difference between USB 2.0 and Firewire.

If the drive is full at 250 GB that gap will be about 10x bigger which is almost 50 min difference, at 25 GB with a 5 min difference.

I forgot to mention that sustained rates were about 22 to 25 MB/s for Firewire on large files with a max peak of 28.5 MB/s, the reason it dropped to 16 average was the internal drive on the Powerbook couldn't keep up and dropped down to 800 KB/s for about 2 -3 min. That problem would be solved with a 7200 RPM internal because of the reduced seek times over 4200 RPM of the laptop drive.

I only noticed the drop for a shorter period (1-2 Min) on USB 2 but I never saw a peak over 17 MB/s and and most of the time it hung around 15 to 16.5 MB/s. So I think that is the limit of USB 2 where I couldn't get to the limit of Firewire with my set up, so it is something to consider.

All of those numbers were from what I was observing on Activity Monitor.

I should have included those observations in my original post, sorry about that.

So I'm still favoring Firewire.

[Wrao]

I always really liked USB as a peripheral connector, ever since I had my first hand-me-down iMac, it just made so much sense, a very good standard. But USB 2.0 trying to step into firewire territory always struck me as weak. At least USB 2.0 is fully backwards compatible with 1.0, I'll still stick with firewire for my external drive needs. (firewire 800 at that! )