knock off a resistor, usb dead now , Compaq Presario 5000

  • Thread starter Thread starter saturnlee
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saturnlee

My sister knocked off one of the tiny resistor R175 that next to the
FW82801AA south bridge. I tried to find the resistor in the computer
case, but couldn't find it.

Now the USB port is completely dead, windows detects the USB port(shows
it in device manger), but nothing show up after i plug the usb devices
in. The mouse and modem don't even light up the LED.

The board is compaq part#:157126-102
SPS - proc Bd ( w / o ) proc BMW - 2 , intel 810, 4 PCI, no AGP, with
sound
Question: Is it possible to detemine the resistor R175' s value?

I look at the layout and guess it may be 22ohm. Any suggestion?
will it work if i just bridge it without any resistor?

If anyone knows the value of R175 right next to the south birdge,please
let me know.

Pictures
http://www.geocities.com/saturnlee/Repair/compaq810/2.JPG
http://www.geocities.com/saturnlee/Repair/compaq810/1.JPG
 
If you have a m/b user manual with a picture of the board magnify it until
you can see R175.
If it's a standard type it will have a colour code on it.
If it's surface mount it will have numbers on it.
If you find them post back.
Also if it is still inside the case you will need to find it in case it
bridges part of the circuit and causes more problems.
 
My sister knocked off one of the tiny resistor R175 that next to the
FW82801AA south bridge. I tried to find the resistor in the computer
case, but couldn't find it.

Now the USB port is completely dead, windows detects the USB port(shows
it in device manger), but nothing show up after i plug the usb devices
in. The mouse and modem don't even light up the LED.

The board is compaq part#:157126-102
SPS - proc Bd ( w / o ) proc BMW - 2 , intel 810, 4 PCI, no AGP, with
sound
Question: Is it possible to detemine the resistor R175' s value?

I look at the layout and guess it may be 22ohm. Any suggestion?
will it work if i just bridge it without any resistor?
Click to expand...

No! If you've got nothing better to go on, I'd suggest a resistor kit,
and first fit a 1M and test, then a 330k, then 100k, 33k, 10k, etc,
testing at each stage. Too low an R may fry something, so work down not
up.


NT
 
My sister knocked off one of the tiny resistor R175 that next to the
FW82801AA south bridge. I tried to find the resistor in the computer
case, but couldn't find it.

Now the USB port is completely dead, windows detects the USB port(shows
it in device manger), but nothing show up after i plug the usb devices
in. The mouse and modem don't even light up the LED.

The board is compaq part#:157126-102
SPS - proc Bd ( w / o ) proc BMW - 2 , intel 810, 4 PCI, no AGP, with
sound
Question: Is it possible to detemine the resistor R175' s value?

I look at the layout and guess it may be 22ohm. Any suggestion?
will it work if i just bridge it without any resistor?

If anyone knows the value of R175 right next to the south birdge,please
let me know.

Pictures
http://www.geocities.com/saturnlee/Repair/compaq810/2.JPG
http://www.geocities.com/saturnlee/Repair/compaq810/1.JPG
Click to expand...

This will not be a lot of help, but here goes...

Reference schematic for Intel 810/ICH0. PDF page 20 has most of
the USB related stuff, and page 14 shows where the page 20 stuff
connects to the ICH0.

http://www.intel.com/design/chipsets/designex/S290657.pdf

Datasheet for ICH/ICH0 82801AA/82801AB. The above schematic
uses 82801AB, and perhaps you can note whether there are
any significant differences by looking at this. There
are some pinout differences between the AA and AB chips,
with the AA multiplexing some signals, while the AB has
separate pins. The differences may not affect the USB.

http://www.intel.com/design/chipsets/datashts/29065503.pdf

Looking at your pictures with the resistors labelled, the
Intel schematic does have 15K ohm pulldowns on the USB
data signals, and 15 ohm series damping resistors. Your
measured value of 22 ohms could be a series damping
resistor with a slightly changed value compared to
the reference schematic.

If your theory is correct, one USB port should still be
working (as its two 22 ohm resistors would be intact), while
the second port only has one of the D+/D- signals connected
to the USB stack, due to the missing resistor.

Good luck,
Paul
 
My sister knocked off one of the tiny resistor R175 that next to the
FW82801AA south bridge. I tried to find the resistor in the computer
case, but couldn't find it.

Now the USB port is completely dead, windows detects the USB port(shows
it in device manger), but nothing show up after i plug the usb devices
in. The mouse and modem don't even light up the LED.
Click to expand...


If it was a USB1 port...now would be a good time to just forget it and
install a PCI , USB-2 controller
 
OK, you're USB shows up because it's detecting the USB ROOT hub within
your southbridge, DO NOT BRIDGE THE GAP WITH NO RESISTOR!!! You will
fry your southbridge

i need to know, are ALL your USB's dead, or just front header or just
rear?
 
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