USB Ports

[Suchy]

How can I check if the USB ports on my machine are 1.0, 1.1 or 2.0 ?
I have XP Pro

[Paul Komski]

Assuming you have USB2 (as PCI to USB Enhanced Controller) under Device Manager there are only two ways that I know of. Firstly, just time how long it takes to transfer a large/largish file. Secondly, some PenDrives change the colour of their LCDs depending on whether they are attached to a USB 1 or 2 port.

[Suchy]

Oh, ok I thought that there is an option that will display what type a given port is.
But Thanks

[Paul Komski]

OK - well as long as you have at least WinXP SP1 (which contains the USB2 software support/drivers) then if you hotplug a USB2 device to a port (on a mobo or card which is not designed nor wired for USB2) then you should (under WinXP) get a baloon from the system tray warning you that you have connected a USB2 device to a USB1 port.

That's the nearest I've ever seen to the OS notifying you. I guess it knows from hardware's plug-n-play settings that the device is USB 2 and times the access so that it knows whether the port itself is also USB2 compatible.

I happen to have a system with front panel USB1 ports and rear panel USB2 ports. My WinXP SP2 does this if a USB2 Pendrive, for example, is attached to a front port whereas there is no such warning with a USB1 mouse in the same position. Since the data transfer rates are some 40 fold faster under USB2 its not that hard to make the differentiation when using devices that involve data transfer.

[Sylvander]

I copied an 837 MB file from my external HDD to the internal one using USB2.

It took 951 seconds = 15.8 min to transfer at about 880 kB/s.

Is that about right?

[Paul Komski]

837,000,000x(1.024^3)x8/951 ~= 7.5Mbits/second and is below the USB 1.1 maximum of 12Mbits/second.

USB 2.0 data transfer should at least approach its 480Mbits/second maximum (and would be measured in Gbytes/minute) though other limitations of one's system could make it a bit less than that.

I would have expected your file to transfer in under 2 or 3 minutes if USB2 was in use throughout. I just copied 654MB of files from my USB 2.0 PenDrive to a SATA 1.0 HDD and it took 92 seconds.

Reference: http://www.everythingusb.com/usb2/faq.htm

[Sylvander]

OUCH! :( :confused:

The drive is definitely running under the "USB 2.0 Root Hub" in Device Manager.
Could it be the speed of the external HDD that's limiting the rate of transfer?
The external HDD is an old ATA/33 I think.
The internal is an ATA/133 HDD on a PCI to ATA/133 controller card.
If so, then perhaps I should buy a new ATA/133 HDD for the external enclosure.

I notice in Device Manager on each of the HDD's there's no tick-box for DMA, no mention of PIO; are they using the CPU to control the transfer or not?

[Paul Komski]

You may have enabled USB2 driver support and have an external USB2 device but was your mobo (or expansion card) designed with USB2 hardware on it - one break in the chain and you drop down to the lowest denominator.

Even straight ATA transfers should reach 4MBytes/second (32Mbits/second) so I doubt if the HDD is at the root of the problem.

Reference: http://www.seagate.com/support/kb/disc/ata_to_ultraata66.html