USB limitations/problems

Archived from groups: alt.sys.pc-clone.dell (More info?)

I've been plagued for more than a week now with USB problems on my Dim
8400. I've had 2 USB printers (one is an Epson R300 which defines a USB
removable disk), an external DVD burner and a couple of external USB2
HDDs for many months without a hiccup. Then I added 2 more external HDDs
last week and the spam hit the fan, e.g., I started having problems
booting from a CD (sometimes the DVD burner is not present, other times
I get file missing or corrupted), USB devices disabled with Code 10, the
Generic USB Hub also shows Code 10, the event viewer shows failing USB
devices with event ID 11 (so I have tried different/new cables,
different USB ports, etc.), etc.

I have moved the DVD burner to an internal PATA port, which gives me
another HDD to connect externally, and scoured Google. I've found a lot
concerning Code 10 on USB devices and have found a temporary cure; but
no matter what I do the situation returns. If all USB devices are turned
off and I turn them on sequentially after booting, everything is usually
fine; but is they're all on when I boot, I *always* get the problem.

My best guess after a lot of fiddling with the computer is that there's
a timing (or collision a la networks) problem with so many USB devices.
I'm considering reinstalling XP Pro, which will insure that everything
is defined anew in the registry; but wonder if it will actually solve
the problem. I also wonder if there are any capacity/timing issues with
USB I'm not aware of, or if certain USB ports are more important than
the others.

Obviously I'm hoping to find a permanent fix for the problem. Any advice
greatly appreciated.

TIA

Archived from groups: alt.sys.pc-clone.dell (More info?)

Ben Myers wrote:

> I suspect you hit a limitation, either timing or throughput. The USB 2.0 spec
> ON PAPER allows for many devices to be connected. It would interesting to know
> if any lab testing USB managed to attach a bunch of devices... Ben Myers

Thanks, Ben, a follow up:

I bit the bullet last weekend and reinstalled XP Pro on a hunch. I
turned on external USB devices in the order I wanted them to appear in
Device Mgr, i.e., the external HDDs first and the Epson R300 printer
(which includes a USB removable drive) and everything is exactly the way
I was trying to get XP to behave before. Never a peep about USB devices
and it makes no difference which is ON or OFF when I boot my computer.
Mission accomplished and I have a very tidy C:\ drive!