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Tony Hwang

Tony Hwang wrote:
(Scott Lurndal) wrote:
Tony Hwang writes:
J Burns wrote:
On 4/28/15 12:37 PM, Tony Hwang wrote:
J Burns wrote:
On 4/28/15 10:13 AM, Tony Hwang wrote:
Snuffy "Hub Cap" McKinney wrote:
I finally learned to check these first before jumping into the
software or running to the computer store. A good lesson for
anyone
else interested...

I have a board in the PC -- don't remember what it's called --
that
plugs into mother board and give me 6 more USB ports. I have
all of
them being used. Yesterday, all the USB devices connected to that
board stopped working. Figured it was the board or bad
connections.
Shut it down and tried pulling it out and back in a few times --
didn't help. So I pulled out the bard and saw the top had a
good 1/16
inch of dust. Brushed it off good with a dry toothbrush, put it
back
in and working again.

Note to self -- try the simple first, dummy.

Just a common sense.

I don't understand. Why didn't you see the dust when you pulled the
board out a few times?

I wonder if it was capacitive coupling between two legs of an IC,
through the dielectric constant of the dust.

I believe dust creates heat build up causing possible over heating.
Excess heat makes things expand. No. 1 enemy for electronics comp[onet
is too much heat.

I don't suppose there's much mass on a USB board. I figured if it was
heat, it would have resumed working when he shut the power off long
enough to unplug and replace the board a few times.

USB chips don't dissipate significant heat, even under load. Not
like a CPU, which can dissipate upwards of 160 watts or more depending
on the clockspeed and SKU.

Most of chips work on standard basic 5V DC.

Where have you been for the last decade? Think 0.8-1.5 volts
for most modern chips (particularly CPUs). Takes less energy
to switch .8 v than 5.0vdc and you can do it faster.

Reduction in voltage comes from mainly much higher density circuit.
Every thing is SMALL and CLOSE each other.(Nano tech.) How many
x-sistors in a Quad core i7 latest gen. CPU?

Now being retired, my pastime is fixing friend's

Ah, that's where.