On Sat, 29 Dec 2007 16:39:50 -0500, Yousuf Khan <bbbl67@[EMAIL PROTECTED]
>
wrote:
>I have two generic 4-****t USB hubs that are supposed to be USB 2.0
>compliant. The older one is fine, works as advertised. Meanwhile the
>newer one sometimes shows up under the USB 2.0 root hub (i.e. "Standard
>Enhanced PCI to USB Host Controller"), or usually it shows up under the
>slower "Standard OpenHCD USB Host Controller" (USB 1.1).
>
>My motherboard (Asus M2NPV-VM) USB ****ts are all USB 2.0 compliant, and
>they individually auto-detect whether they need to switch down to USB
>1.1 speeds. I'm using a Microsoft tool called UVCView under Windows XP
>to display the details of the USB devices, including the hubs and
roothubs.
>
>According to UVCView, the older hub and newer hub seem to have the same
>chipset vendor (idVendor = "Genesys Logic, Inc."), although externally
>they look quite different and have different brand names. So I'm not
>sure why one would be consistently USB 2.0 compliant, while the other
>one is not.
>
>Now another interesting thing I noticed is that the inconsistent hub
>will only show up as USB 2.0-compliant after I boot into Windows after
>having previously rebooted from Ubuntu 7.10 Linux (dual-boot system). So
>maybe Linux does something to the device that puts it right. But when I
>list the devices while in Linux I see that it is listed under USB 1.1
>just like when in Windows. I have no idea why Linux leaves the hub fixed
>for Windows, but doesn't fix it for itself?!
>
>Any idea what's going on with this hub?
>
> Yousuf Khan
Crappy cable? I've seen a few times a 2.0 device gets downgraded to
1.x when connected with a substandard cable. A good quality cable
(try Belkin) solved it for me.
Oh, one more thought - check where the hub in question was made. If
it's China, that explains it. If they deliberately use led paint for
children's toys (saves a fraction of a penny per toy vs. non-toxic
one), and conveniently forget to put cord into tires (saves both
material and labor - a few bucks total per tire - who cares if people
die when it blows out), you can expect similar "quality" materials and
workman****p from the hub.
NNN
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