USB Power Short?


I put together a home build yesterday roughly based on the non-gamer build posted here:

The case suggested was out of stock, so I went with the following:

Everything started fine, I installed Windows and have been working on the machine with no problem.

However, I attempted to plug in a wireless keyboard/mouse connector to the USB input on the front of the case. Occasionally when I did this, the machine would either turn on (if it was off) or turn off (if it was on).

I'm obviously thinking there is a short somewhere, but I'm not sure how to determine where. It doesn't happen if I unplug the USB from the MOBO. I tried switching to a different USB set on MOBO and the same thing occurred.

Any ideas on how to track down the problem?
9 answers Last reply Best Answer
More about power short
  1. ur usb is grounded out if ya good at soldering then remove "sister" board from the case and take the usb off clean the old solder off clean the area with rubbing alcohol from a cotton swab and use good flux on a new cotton swab and resolder it back on and try it again should solve it
  2. Best answer
    x may be right but, before I read that answer I was thinking your "soft power" switch connection (poles) are prolly bridging on the chassis, whenever the "force of insertion" (ah!) flexes the switch (or the little printed circuit brd the switch is mounted on.)

    = maybe?, eh? =
  3. I mean, the solution *might* be as simple as taping a cardstock busines card on the chassis, or between the chassis and the switch (or circuit board).

    = Doh ! =
  4. Here's a fun thot ...
    Get a bright light and a big magnifying glass and strip away as much as the facade/facia
    (pretty plastic panels) as you can.

    "Watch" what happens. ?

    = ? =
  5. Thanks for the input, I double and triple checked all of the wiring on the USB connection and it all looks OK. I hadn't considered that the USB circuit board could be bridging with the power switch.

    I have removed the USB panel from the case for now, I will try to verify that the USB was bridging with the power switch.

    I have soldering experience, but don't actually own one myself, this could be a good excuse to buy one though.
  6. I am thinking it is more of a physical "things-touching" issue and should not require your special solder skills ... replace the case, should it come to that ...

    ... Shouldn't require more than a carefully placed piece of masking or electrical tape. Just cover the whole back of the board and around/near the USB ... anything with exposed metal or solder ... just insulate the chassy, USB, and Swtch board all from each other, inasmuch as seems possible.

    = Best-o-Luck ! =
  7. and ... (i wish I could see it) ... I was visualizing that the flexing of the mounts/panels was bowing whenever you pushed in on the USB port.

    A short in your USB cable or connections might cause a system reset or a power-recycle as well, tho. (tho I have not seen this, I *have* seen mobos reset when not properly grounded or when I've "missed" with a screwdriver or dropped screws on the wrong trace, when live.

    = Al =

    = Al =
  8. Best answer selected by CMack124.
  9. Thanks for the help, I went back and plugged in the USB circuit board to the MOBO without mounting it on the front panel of the case. I had no problems using the USB port like this. Something must be shorting on the front panel itself between the USB board and the power/reset switches. I will try some quick fixes to stop the short, if it comes down to it I will contact the manufacturer and try to get a replacement.

    Thanks again for the help.
Ask a new question

Read More

Build USB Systems Product