Re: External USB20 HDD writing speed?

<wong-lawrence@xxxxxxxxxxx> wrote in message news:%23TCTn7HwGHA.4612@xxxxxxxxxxxxxxxxxxxxxxx
"Loren Pechtel" <lorenpechtel@xxxxxxxxxxxxxxxxxxx> wrote in message news:%230hbHpjvGHA.4160@xxxxxxxxxxxxxxxxxxxxxxx
On Fri, 11 Aug 2006 23:33:17 +0200, "Pvest" <no@xxxxxxx> wrote:

I have a Maxtor 300Gb USB 2.0 harddrive and when I did a benchmark (with FreshDevise), it gave med this speed:

Write 1.1 Mb/s,

Read 60.5Mb/s speed.

I also know that the spec for USB2.0 480Mbps, but not really sure how to read different benchmark speed I get!?

But can anybody confirm that a USB 2.0 writing-speed on 1.1Mb/s is what I could expect, or is there anything wrong here??

Something's very wrong.


At 300 GB capacity, I'm going to assumt it is a full out 3.5" drive.

if it is an IDE drive inside, it should run at 500 MB/s, SATA-I runs at 1.5 GB/s, and (in your case the most likely) SATA-II runs at 3.0 GB/s. Take note these are maximum data rates for the HDD ONLY.

Going through USB 2.0, the maximum is 480 Mbps or MegaBITS per second, not megaBYTES per second. The data transfer rate is different than the transfer rate of the hard drives.

There are 8 bits in a byte. So, at 480 megaBITS per second translates into approximately 60 megaBYTES per second (Divide by 8).

So, although your write speed does seem a little slow, for an exterenal drive, your read speed sounds like it's on par. Your speed cap is caused by the USB transfer rate and not the Hard drive.



--
Lawrence Wong
Computer Systems & Networking Technology Student
Centennial College, School of Science & Technology
Toronto, Ontario, Canada


A small correction: EIDE drives can run at a maximum transfer rate of 133 MB/s, not 500.



--
Lawrence Wong
Computer Systems & Networking Technology Student
Centennial College, School of Science & Technology
Toronto, Ontario, Canada

.

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