I am having some problems in my PC after I have recently added some USB
devices to my PC:

-  Sometimes when I reboot the PC, I see a blue screen and saying
something about IRQ something. I believe this means I have a IRQ
conflict. Sometimes I can get around with this problem by rebooting to
the last-known-good-configuration. But this doesn't always work.

-  When I reboot the PC, the boot-up time seems to be much longer than
I have expected.

-  The mouse feels like kind of sticky. Likewise, keystroke seems to
hesitate to show up. (Both the mouse and the keyboard are USB devices)

-  Video playback is stuttering regardless which video players I use.

My PC has two kinds of USB: USB-1 (comes with the PC) and USB-2 (I
added this to my PC using a Firewire/USB2 adapter. I have been using
these two types of USB for at least 2 years without any problem.

I have recently added the following USB devices to my PC:
-  USB-UIRT device to transmit infra-red signal to change TV channel.
-  UPS backup device that transmit its status to my PC using a USB-1
connection.
-  A fax modem that I disconnected a while ago, and I recently added it
back to the PC.

I had tried unplugging some of them. But that didn't help.

I would like to find an approach to fix this problem.

Thanks in advance for any help.

Jay Chan

jaykc***@hotmail.com wrote in news:1109603742.074227.37130
@f14g2000cwb.googlegroups.com:

Just a quick first suggestion: shut off USB-1 on the motherboard and
remove their controllers. Since you have the USB-2 card you dont need
them. Also, shut off all the standard serial ports if you dont use them
either. All take IRQs. Otherwise you are using 2 for USB on the MB, and 2
for the card), AND however many you are using for Firewire. It adds up.

Prior to XP, so I hear, PCI location makes a big difference, and the best
solution sometimes is to switch them around until you find a setup that
works. From what I understand, 1 sometimes 2 PCI slots are tied into AGP
and they will share interupts (maybe someone can say if I misunderstood
this). Also, if you can do without the USB fax modem, great. If you need
it, look into a PCI card instead... faxmodem cards are cheap and even
just as likely you might know someone who has one laying around. You
might even have an ISA slot that you never knew what to do with.

Cheers

Thanks for the suggestion.

I have already disabled the built-in serial port and printer-port.

The idea of switching the PCI slot for the USB card sounds promising.
If the AGP video card and the USB card shares the same ISQL, this may
explain the reason why video playback is stuttering.  This will be the
first thing I will try.

The idea of removing the USB Fax Modem is also good.  I already has a
PCI Fax Modem.  I cannot use it in my PC because my PC is running out
of PCI slot (Thanks Dell for giving so few PCI slots in their PC).  I
will have to get my very old Pentium Classic out from mothball, put the
PCI Fax Modem into it and use it solely for sending and receiving fax.
Although this alone likely will not fix the problem (because I have
already tried removing it once before), simplifying the configuration
in my PC is a good idea to avoid any future problem.

As of disabling the built-in USB-1 ports, I will try this last.  I am
running very low with USB ports.  Moreover, the built-in printer port,
mouse port, and keyboard port are all using the built-in USB-1.  I will
be hesistate to disable it.

I will ask around in Dell PC newsgroup to see if they know which PCI
slot to avoid.

Thanks.  I appreciate that.

Jay Chan

jaykc***@hotmail.com wrote in news:1109685851.666168.266060
@f14g2000cwb.googlegroups.com:

Try a USB hub.

So there will be one physical connection to the computer... then to the
hub... then to each device. Usually there are 4 ports, but it can go much
higher. You can also daisy chain them I believe, but hubs sounds much more
usable.

I am assuming you have more than 1 on the MB... even disabling one of them
would help. But also, maybe attach the keyboard and mouse to a second one
on the card.

Turn out your idea of disabling the built-in USB-1 is a good one.  I
have disabled the built-in USB-1 on the motherboard (and unplugged all
the devices connected to USB-1), and most of the problem goes away.
Now, I don't have any sticky mouse, any sticky keyboard, any
IRQ-conflict at boot-up.  And the PC just runs MUCH faster.  Thanks for
the good suggestion.

Turn out the keyboard and mouse are not USB devices.  That's why I can
disable the USB-1.

I will buy a USB-2 hub later today and try connecting those devices
back to my PC.  I hope the problem will not re-surface.

The only thing that still doesn't work well is MPEG2 video playback.  I
still have stuttering problem when I play MPEG2 files.  Seem like this
is a different problem.  I will need to spend some time doing trials
and errors to find the cause of this problem.  If all fail, I may need
to buy a new video card that has hardware-assisted video playback.

Jay Chan

I have added a USB-2 hub, and I connect all the devices that used to be
connected to USB-1 into the USB-2 hub.  No problem.  Seem like the
USB-1 doesn't work well with USB-2 if I start adding more and more USB
devices (they co-exist fine when I only have a few USB devices).  OK,
one fixed.

I have identified the video stuttering problem has to do with the
combination of Beyond-TV problem and McAfee firewall / anti virus
software.  In other words, this is a software problem and is not a
hardware problem.  Now I am sure that I will find a solution soon.

Jay Chan

jaykc***@hotmail.com wrote in news:1110297914.781877.51110
@l41g2000cwc.googlegroups.com:

Very cool. If in the future you need even more ports, I believe you can
daisy chain hubs branching off one main hub... such as the one you just got
going to four more... giving you a total of 16 ports.  Well... either that
or just get a new one with more than four.

Kev wrote:
Show quoteHide quoteThe problem is power.  Each USB root hub has only 500mA current
available and some of that is reserved.  If you hang every USB device
onto hubs, unless the hubs are self-powered, it is likely that there
will be a power shortage at some point.

Q

i*@comcast.com:

true true. better than those cards with 4 ports, from what I hear about
them. ;o)

I think I am maxed out for now. The hardware is not maxed out; I am
just mentally maxed out. I don't want to see any more wire going to the
back of the PC; there are many many cables already (6 USB devices
connecting to my PC).

Jay Chan

Kev wrote:

Show quoteHide quoteHave you tried using the hardware device manager?  On Win2K, right click
  My COmputer>Manage>Device Manager.   Look for question marks and
yellow indicators.  Pull boards until these go away.   Or at least,
reconfigure to eliminate the conflicts.  Expand all the subscreens to
find memory conflicts and IRQ problems.

I checked this already, and I didn't see any yellow question mark in
Device Manager.  This is why I am really puzzled.

Jay Chan

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