About how Fast USB with PATA

thideras said:

That is the USB limitation, around 23mb/sec. You won't get faster with a USB 2.0 device.

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Psycogeec said:

I have a media box that has in it a 600G 5400r segate drive, formatted for NTFS in larger clusters like 16-32k the drive connects via Parellel connection. it is powered externally.
it is connected via the USB 2 , passes through one "hub" item in a monitor.

it gets speeds of about 25MB/s (non-burst) is that about right, or terribly slow?
(because it seems terrible slow to me :-(
how fast are some of those boxes like MyPassport and stuff like Small 2.5 drives that are self contained?

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USB 2.0 has a raw data rate at 480Mbps, and it is rated 40 times faster than its predecessor interface, USB 1.1, which tops at 12Mbps. Originally, USB 2.0 was intended to go only as fast as 240Mbps, but in October 1999, USB 2.0 Promoter Group pumped up the speed to 480Mbps.

As far as we know, effective rate reaches at 40MBps or 320Mbps for bulk transfer on a USB 2.0 hard drive with no one else is sharing the bus. Flash Drives seem to be catching up too with the some hitting 30MB/s milestone. For all we know, USB interface could become become the bottleneck for flash drives as early as 2008.

Additional notes from Alex Esquenet - our engineer friend based in Belgium: "A fast usb host can achieve 40 MBytes/sec. The theorical 60 MB/sec cannot be achieved, because of the margin taken between the sof's (125 us), so if a packet cannot take place before the sof, the packet will be rescheduled after the next sof. On top of that, all the USB transactions are handled by software on the PC. For instance, a USB host on a PCI bus will send or receive the data via the PCI bus; the stack will prepare the next data in memory and receive interrupt from the host."

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RJARRRPCGP said:

60 MB/s is the max, AFAIK. (480 Mbit)

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BigAndrew said:

I'm ordering parts off of newegg to build a new rig and i made sure to get a mobo with USB3, Will an external hard drive connected with USB3 be able to reach speeds higher then that?

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moz_21 said:

With USB3 you'll be limited by the hdd's speed. (Excluding SSD's)

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BigAndrew said:

Oh ok, cool... it would be pretty nice to have a fast hhd as a external but for the price it isn't worth it to me, they have some pretty good deals on 2TB Hdd but their like 5400rpms instead of 7200

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moz_21 said:

Why not go eSATA?

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BigAndrew said:

I dunno... I dont really know anything about eSATA I'm still a newb, But i'm trying to learn one thing at a time

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moz_21 said:

Yeah I don't know much about it either, except USB3 is pinning to overtake it.

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