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Edris Kamali · April 6th, 2004, 07:11 PM

Hi;
I am running out of space in my computer Hard Disk and know I am thinking of buying a external hard drive. I would like to know if the speed of hard disk with USB2 or Firewire is faster than an IDE hard disk.

thank you

George Ellis · April 6th, 2004, 07:48 PM

A Firewire or USB attached drive is an IDE drive. The external drive will usually not be faster than the internal drive unless you have an old machine (circa 1996). Go with the Firewire as Firewire is faster than USB (even though on paper, USB would be faster.) Some drives do both, which can be beneficial if you need to take it somewhere to 'share' a file as many will at least have USB.

Edris Kamali · April 6th, 2004, 08:06 PM

Thanks George; Still I don't know how an internal HDD with transfer speed of 66mbs is faster than 480mbps speed of firewire or usb-2. Perhaps there are other factors that I am not aware of.

Rob Lohman · April 7th, 2004, 03:42 AM

You can roughly divide mbps or mbit/s or Mb/s by 10 to get a
rough estimate of the MB/s. So 400 mbit firewire will have a
maximum transfer speed of 40 MB/s. But I doubt you'll see those
numbers in the real world. I also doubt your harddisk will do a
sustained 66 MB/s.

In theory a firewire *connected* (which is a better word) harddisk
can definitely be slower then when the drive would've been
placed internally. In the real world I think you'll see it is also a
bit slower.

Whether that matters to you is another thing. DV is 3.6 MB/s and
I would say that you would at least need a 5 MB/s sustained
write speed to not drop any frames. Any current harddisk on a
firewire or USB 2 (make sure your computer is USB 2 as well!)
connection should capture / playback DV without any problems.

So for normal work this slightly slower speed will not be any
problem at all. If you routinely need to transfer 10+ GB from one
drive to another it might costs you some minutes.

George Ellis · April 7th, 2004, 06:11 AM

The confusion is you are comparing megabits to megabytes. There are 8 bits in a byte. So, Firewire is stated as 400 megabits per second. An ATA-66 drive transfers at 66 megabytes per second (theoretically), which is 528 megabits per second. Megabits is correctly listed as a little 'b' while megabytes is correctly listed as big 'B'.

Most IDE drives tend toward around a 30-40MB/s sustained transfer rate. The usual, best sustained rate for most Firewire connected drives is around 25MB/s. USB is usually closer to 20MB/s.

April 6th, 2004, 07:11 PM	#1
Edris Kamali New Boot Join Date: Mar 2004 Location: Molbourne - Australia Posts: 6	Video storage Hi; I am running out of space in my computer Hard Disk and know I am thinking of buying a external hard drive. I would like to know if the speed of hard disk with USB2 or Firewire is faster than an IDE hard disk. thank you __________________ Kamali

April 6th, 2004, 08:06 PM	#3
Edris Kamali New Boot Join Date: Mar 2004 Location: Molbourne - Australia Posts: 6	Video storage Thanks George; Still I don't know how an internal HDD with transfer speed of 66mbs is faster than 480mbps speed of firewire or usb-2. Perhaps there are other factors that I am not aware of. __________________ Kamali

April 7th, 2004, 03:42 AM	#4
Rob Lohman RED Code Chef Join Date: Oct 2001 Location: Holland Posts: 12,514	You can roughly divide mbps or mbit/s or Mb/s by 10 to get a rough estimate of the MB/s. So 400 mbit firewire will have a maximum transfer speed of 40 MB/s. But I doubt you'll see those numbers in the real world. I also doubt your harddisk will do a sustained 66 MB/s. In theory a firewire connected (which is a better word) harddisk can definitely be slower then when the drive would've been placed internally. In the real world I think you'll see it is also a bit slower. Whether that matters to you is another thing. DV is 3.6 MB/s and I would say that you would at least need a 5 MB/s sustained write speed to not drop any frames. Any current harddisk on a firewire or USB 2 (make sure your computer is USB 2 as well!) connection should capture / playback DV without any problems. So for normal work this slightly slower speed will not be any problem at all. If you routinely need to transfer 10+ GB from one drive to another it might costs you some minutes. __________________ Rob Lohman, visuar@iname.com DV Info Wrangler & RED Code Chef Join the DV Challenge \| Lady X Search DVinfo.net for quick answers \| Buy from the best: DVinfo.net sponsors

April 6th, 2004, 07:48 PM	#2
George Ellis Trustee Join Date: Feb 2004 Location: Suwanee, GA Posts: 1,241	A Firewire or USB attached drive is an IDE drive. The external drive will usually not be faster than the internal drive unless you have an old machine (circa 1996). Go with the Firewire as Firewire is faster than USB (even though on paper, USB would be faster.) Some drives do both, which can be beneficial if you need to take it somewhere to 'share' a file as many will at least have USB.

April 7th, 2004, 06:11 AM	#5
George Ellis Trustee Join Date: Feb 2004 Location: Suwanee, GA Posts: 1,241	The confusion is you are comparing megabits to megabytes. There are 8 bits in a byte. So, Firewire is stated as 400 megabits per second. An ATA-66 drive transfers at 66 megabytes per second (theoretically), which is 528 megabits per second. Megabits is correctly listed as a little 'b' while megabytes is correctly listed as big 'B'. Most IDE drives tend toward around a 30-40MB/s sustained transfer rate. The usual, best sustained rate for most Firewire connected drives is around 25MB/s. USB is usually closer to 20MB/s.