USB Unknown device

[hhmcsv]

Hi Group,
continuing the misery about USB-ports supposed to be 2.0 but acting as 1.1, I at least for now have solved that one using the "Driver Dance" described in an earlier thread.
But I have another problem with the USB-ports on my TP T40:
Some units will not function properly.
My LaCie mobile hard drive, which before has functioned on the T40 (and is still functioning on the desktop PC) is now showing up as "unknown device" upon connecting to the T40. I have tried to uninstall /reinstall driver, but it does not seem to lead anywhere.
I also have a USB/Com-port cable, which has problems functioning connecting to a sattelite navigation device.
There is no error messages on device manager.
Any ideas anyone?

[smugiri]

There are at least two (if not more) issues at hand here.

- the ports are dying. This takes a while (and is related to static electricity and the chipset) but once you start doing the driver dance, they WILL definitely die.

- draw on these devices is more than 100mA - this causes the port to shut down

Bottom line is that the SouthBridge (and thus the USB ports) on the machine will certainly die or go back to USB 1.1 speeds and the only solution at that point will be some sort of PCMCIA card or a new board.

[hhmcsv]

Hi Steve,
Thanks for the not-so-optimistic reply. I have already bought a PCMCIA usb-card as a workaround, but it is a clumsy solution.
But never mind, it looks like I will have to live with this fault, as my T40 is out of warranty and getting a new mobo (with the same potential fault) does not sound like a good solution.

It does puzzle me a little, that none of the diagnostic tools (device manager, Intel USB tool) shows any malfunction or other diagnosis of the below-normal functioning of the ports.

I also find it strange, that my digital TV-tuner works fine (it requires usb 2.0 speeds to produce flicker-free reception) and draws some current for supply) wheras the USB-Com-port cable does not function.

But as I said, I will probably have to live with it!

[coreman]

Well here is a more optimisitic reply...from someone who lived with this problem for more than (6) months...

1: I don't think the "driver dance" is symptomatic of "dying" USB ports. I was able to do the dance for (6) months and successfully get my ports back to USB 2 when needed. If you want to measure your USB transfer speed(after you get your devices recognized, see point (2) below), please locate HD Tach, a free software that produces hard numbers on the read speeds of disk drives, both external and internal.

I finally replaced the mobo only because it failed for the cracked solder joint under the GPU (most likely caused by flexing of the flimsy case)...and after replacing (2) mobos, Lenovo was finally able to return to me a fully working Thinkpad.

So in light of your machine being out of warranty, there is no real reason for the "driver dance" to symbolize USB port failure...my USB problems were exactly timed to my upgrading to Win XP SP2 as well as the BIOS, and embedded chipset. And even though the problem has been corrected with a new mobo (I don't know what else they did but they certainly did some software changes), I am still not convinced it is solely a hardware failure...

BTW, the ports shut down when current draw exceeds 500ma, not 100 ma...

2. I've also experienced "Device not recognized" failures both on my T30 and T41...each time I found that the USB cable was at fault. When I changed cables, the various devices were able to successfully mount.

If you are like most, you probably have a dozen or more cables that will work on your USB devices...I had to sort through the ones I had and toss out the ones that gave problems. Now I have (2) that I use all the time (USB to mini)...

2A. Another reported source is using a USB Hub, which I don't use, but is also very easy to check out...just plug straight into PC.

And there are many more sources reported on Internet as well as some specific ones that Microsoft has written patches for...