External HD casing speeds

[skisteven1]

I'm looking at purchasing a external HD casing such as this one here

The problem is, I plan on using it for alot of disk-intensive operations (video editing and live capture). I know that when my 7200rpm hd is plugged straight into the mobo, I have very little problem with speed (drop 90 frames over 2hrs, capturing 30fps). But since it does drop a few frames, I believe that it's just barely fast enough to work. Any idea on how well a HD in this enclosure would fair? USB 2.0 tops out at 60MBytes/sec, but what's the average? My incoming video streams are about 25MByte/sec.

Thanks for any help you can offer.

 

[elzmaddy]

I would also like to know. What's a realistic transfer speed in MB/sec to a USB 2.0 connected external drive?

 

[EeyoreX]

I think with USB 2.0 or IEEE1394 the performace should be about the same. Peak internal hard drives are also about 60MB/s, nowhere near the max ATA100 or ATA133 spec'd speeds. And that is still peak/burst speed, not normally sustained rates. So if the max USB 2.0 speed is about that I should think performance should be about the same. I haven't used any extrernal enclosures, but from what I've heard they are generally acceptable.

\Dan

 

[skisteven1]

Originally posted by: EeyoreX
I think with USB 2.0 or IEEE1394 the performace should be about the same. Peak internal hard drives are also about 60MB/s, nowhere near the max ATA100 or ATA133 spec'd speeds. And that is still peak/burst speed, not normally sustained rates. So if the max USB 2.0 speed is about that I should think performance should be about the same. I haven't used any extrernal enclosures, but from what I've heard they are generally acceptable.

\Dan

That's what I was thinking, but I wasn't sure. Does anyone have any numbers on actual speeds when copying a file to an enclosure like this one?

 

[RalfHutter]

Search for the user named "Eug" and PM him. He can tell you more about Firewire vs. USB2.0 external drives than you'd ever want to know.

The bottom line is STAY AWAY FROM USB 2.0 and go with Firewire. Firewire has almost twice the real-world transfer speed of USB 2.0 due to the overhead (inefficiency) of USB 2.0. It's something on the order of 20MB/sec vs. 40MB/sec, real world.