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 From: Jun Tangunan
  Where is Jun Tangunan?
 Jun Tangunan
 To: Samir H.
  Where is Samir H.?
 Samir H.
Subject: RE: USB & USB 2.0 ?
Thread ID: 288941 Message ID: 289057 # Views: 53 # Ratings: 0
Version: Not Applicable Category: Other
Date: Tuesday, December 28, 2010 7:53:17 AM         

> Hi all
> Does anybody know about USB 2.0? I can't upload yet the picture of the computer I'm speaking about, but it's similar to the image below, with the difference that the first item is:
Intel(R) 82801DB/DBM USB 2.0 Enhanced Host Controller - 24 CD

> There are 3 more "Intel... USB" but without "2.0"
> Does it mean that only 1 usb port is fast (USB2) ?
> How do I know if a usb port really uses 2.0 speed? Sometimes XP says "This device can perform faster, please do...", then I know it's not a USB 2.0, but on some computers XP says nothing, eventhough ports are USB2.0 but not correctly installed (getting only USB 1 speed).
> For example on this computer, (SIS MoBo), I can read USB 2.0 on the motherboard, but speed is definitly USB 1.0, and XP doesn't give any warn messages.
> So when I attach my thumb-drive to the computer, how can I know if I'm getting USB2.0 speed?
> Regards
> Samir

You will know if you see the word 2.0 :-U

Kidding aside, if you see the word "Enhanced" then that is 2.0.

Another way to test is to try plugging in a mass storage device like a harddrive. Get a cable that has two chords on one end. If you plugged one chord and it is not easily read by the port, it might be 1.0. To test further, plug the extra chord into the next USB port (now you are plugging both cables into two ports) and if it suddenly works, then definitely you have 1.0 on your machine.

I suspect that the reason for that is USB2 supplies more power than USB1. And when you are plugging the mass storage device to a USB1 port, it cannot supply enough power to spin the hdd head properly (if you listen you will hear clicking noises inside the hdd). When you combine the powers supplied by two USB1 ports, then hdd head can spin properly. That is also the reason why some USB chords have two cables split at the end.



USB & USB 2.0 ? Posted by Samir H. @ 12/27/2010 7:26:07 AM
RE: USB & USB 2.0 ? Posted by Jun Tangunan @ 12/28/2010 7:53:17 AM
RE: USB & USB 2.0 ? Posted by Samir H. @ 12/28/2010 8:17:00 AM
RE: USB & USB 2.0 ? Posted by Jun Tangunan @ 12/28/2010 8:29:34 AM
RE: USB & USB 2.0 ? Posted by Glen Villar @ 1/1/2011 7:13:35 PM