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bgd

macrumors regular
Original poster
Aug 30, 2005
237
11
SG
For an external drive it seems that USB 2.0 is the better choice over Firewire 400 because of speed. Or am I missing something?

External drive will only be used as a backup.
 
A little bit of confusion, but it is common, so dont feel bad.
USB 2.0 has a faster max speed than FW 400, but FW is capable of reaching 400mbps and sustaining it, where as USB 2.0 speed will go up and down. It never hurts to have a external that has the capability to do both though.
 
USB data has to travel through the CPU, where as FW is totally independent. So for large file transfers, FW is overall faster and puts less load on your computer. :)

-Zach
 
USB 2.0 also puts a higher load on the main processor than FW400, which works fairly independently, e.g. you don't need a computer for some peripherals. Slower processors will achieve better results with FW400.
 
faintember is right - a USB 2.0 will hit a max speed of 480Mb/s but cannot sustain it - a FW400 drive can do 400Mb/s but continuously. The USB speed is dependent on the other apps the mobo is running - it doesn't have a dedicated bridge.
For best results get a triple interface drive - FW400, FW800 and USB 2.0 - which should see you right for a while.
 
As stated, FW is better for sustained transfers....especially around video. Also better when having multipe devices (ie: 3 external hds).

I'm looking at getting a LaCie external, and will likely get triple interface. Nice to have USB in case, but I will be connecting to it via FireWire
 
Just so you know, neither FireWire or USB2 will get anything like their top speeds. You'll be lucky to get 30 or 40Mbps
 
greatdevourer said:
Just so you know, neither FireWire or USB2 will get anything like their top speeds. You'll be lucky to get 30 or 40Mbps
Are you talking about Megabits or Megabytes? 8 Megabits = 1 Megabytes so 400 Megabit/s = 50 Megabytes/s
And yes I know the confusion about megabits and megabytes etc :p
 
greatdevourer said:
Just so you know, neither FireWire or USB2 will get anything like their top speeds. You'll be lucky to get 30 or 40Mbps

That's not precise. The electronics will, but the drives themselves won't manage the top speeds.
 
greatdevourer said:
Just so you know, neither FireWire or USB2 will get anything like their top speeds. You'll be lucky to get 30 or 40Mbps

I get 17 MB/s (135 Mb/s) reading from my external USB2.0 drive and 15 MB/s (120Mb/s) writing to it.
 
One more reason firewire would be better; if you want to create a bootable backup on your external drive you need it to be a Firewire connection for it to boot from. Mac's won't boot from USB
 
I have always had bad luck with USB drives. Even when I was a windows user. I would rather spend a little more and get a FW drive.

I would say that Firewire is more reliable, does anyone agree or disagree with this point? I think USB sucks. It is only good for keyboards, mice and low tech peripherals.
 
As far as speed goes, I get 32-34 MBytes/sec over FW400 and 50-52 MBytes/sec over FW800. I've never tested USB 2.0... I should do it sometime. I know it'll be slower than FW400 but I wonder how much slower.
 
OK that got my curiosity going. I tested using xBench the same drive I ran the FW800 test on. The USB 2.0 was getting 16 MBytes/sec. That is only half the speed of the FW 400 test I ran! I wasn't expecting it to be that much slower!
 
USB sucks. Not because its 2MB per sec slower than firewire, but because its low-power. Ugh, you don't know how annoying that gets. Damnit! I wish everything was firewire so you can power larger more complicated things other than a mouse.

The only advantage using USB, is the 'theoretical' speeds, but the amount of devices that it can support. But I don't know anyone with 127 hardrives :rolleyes:
 
DeSnousa said:
How do you find out how fast your external reads and writes?
Use xBench, its a free system benchmark tool.

I went back and ran the tests again just to make sure I wasn't getting the numbers wrong. I've got a LaCie Triple Interface drive, so its the exact same drive and the exact same powerbook running the tests. Here were my results:

Read Speeds:
48 MBytes/sec - FW 800
38 MBytes/sec - FW 400
18 MBytes/sec - USB 2.0

Write Speeds:
51 MBytes/sec - FW 800
36 MBytes/sec - FW 400
27 MBytes/sec - USB 2.0

I'll post the full results below if anyone wants to see them. Its 3 pdf files inside 1 zip file.
 

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blaskillet4 said:
USB sucks. Not because its 2MB per sec slower than firewire, but because its low-power. Ugh, you don't know how annoying that gets. Damnit! I wish everything was firewire so you can power larger more complicated things other than a mouse.

The only advantage using USB, is the 'theoretical' speeds, but the amount of devices that it can support. But I don't know anyone with 127 hardrives :rolleyes:
I like USB for some things. For instance, I run my printer, mouse, and some other stuff into a USB hub. That way all I have to do is unplug one cord when I want to detach all the accessories from my PB and take it to class. But when I'm doing video, I definitely hook up my FW hard drives cause I need as much speed as I can get working off an older G4 processor.
 
Heb1228 said:
I like USB for some things. For instance, I run my printer, mouse, and some other stuff into a USB hub. That way all I have to do is unplug one cord when I want to detach all the accessories from my PB and take it to class. But when I'm doing video, I definitely hook up my FW hard drives cause I need as much speed as I can get working off an older G4 processor.


I understand, but if I recall, firewire can support ~64 devices connected on to a hub just like USB, the only reason (I'm assuming) that almost everything is USB, is because its extremely popular (intel)... What would be nice is if firewire was used to the extent USB is used. All I miss using USB is the high power that firewire provides (not to mention its faster in the real world).
 
blaskillet4 said:
All I miss using USB is the high power that firewire provides (not to mention its faster in the real world).
I feel ya.

Ok I'm really a geek, but those benchmarks I just ran... yeah i used Keynote to make a chart out of them, here it is if you want to see it.
 

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blaskillet4 said:
All I miss using USB is the high power that firewire provides (not to mention its faster in the real world).

Higher power transmission would just end up asking more power from your computer power supply, with higher temperatures inside etc., or hubs with external power supplies.

I use a Canon scanner LiDe80, power-supplied by the USB-hub. It's fine, but I know it reduces my available power for other devices, there's a limit somewhere.

I guess I'm fine with my independent power-supplies for my big USB and all my FW devices... :rolleyes:
 
my canon bus powered scanner has always been flakey and caused sleep problems. firewire owns usb 2's ass, i'm glad i got a motherboard with fw 400 and 800 on it for my pc.
 
Hector said:
my canon bus powered scanner has always been flakey and caused sleep problems. firewire owns usb 2's ass, i'm glad i got a motherboard with fw 400 and 800 on it for my pc.

Mmm, maybe that's why my iMac refuses to sleep all the time... :confused:

I'll unplug the scanner when it's not used then (what a technological achievement !) :eek:
 
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