USB Short Circuit??

hey all,
so my desktop that I built in the summer is doing something funny. It started a few weeks ago and happens off and on, not every time. Basically, sometimes when I plug something into the USB port the graphics (onboard) stop working. The monitor shows no input, but the computer *seems* to still be running. None of the fans stop and all the lights are still on. I am forced to restart it and then it works fine. It hasn't happened with the rear USB ports yet, but I don't often plug anything into them as it is much more convenient to plug into the 2 front ports. It happens with both front ports; I've tried wiggling the wires and reattaching them to the Mobo but it hasn't seemed to make any difference.
Obviously i can just stop using them, but I'd really like to keep them!
My PSU is a 500watt so I don't think that is the problem, especially since it will start up fine with the usb plugged into the front.
Any ideas on how to test it to narrow down the problem exactly, or how to fix it??
Thanks,
*EQL*

 

Greetings, evil_queen_lisa.

Those front ports can be a PITA - it's as if mobo manufacturers had to hang a bag on the board to provide support for front ports. They're usually separate circuits, so problems with the front ports can have absolutely nothing to do with the rear ones.

This could be a tough one: shorts can drive you nuts, especially if they're intermittent.

I use something like this to tie into my rear ports - sure does make it simple to interchange devices.

 

I doubt there's a short is the USB port as it works,it sounds more like a software or motherboard problem?Can you post your OS In all OS's go to device manager and check the USB ports are working properly click the devices it should say "The device is working properly" and there should be no exclamation marks.

First I'd try safe mode and use the USB ports see if you can get it to crash,find the name of your motherboard,download and update the video and chipset drivers,go into your bios and check USB keyboard and mouse support is enabled,make sure all USB ports are enabled,you may also want to try loading optimized and safe bios defaults.

 

my gut feeling is that it is a short. Last time it happened i hadn't even plugged the usb cord in yet, it just touched the metal on the outside. i'm updating my graphics and will do my chipset in a minute. Lets see what happens...
*EQL*

 

Hmmm?That's very strange :confused You just touched the metal on the outside with a USB plug and the video cut?Was the USB plug halfway in?The metal outer case on a USB plug is dead i.e not connected to anything,if one of the pins does short on the metal socket and then the socket touches the case it could earth,that's the only thing I can picture happening,check the the integrity of the 4 pins inside the usb port,beyond that you would need to test the whole USB cable+socket with a multimeter.

Just to double check it does this with different devices?You could try removing the front usb ports from the case to rule our case short 'usually just two screws'and obviously you could connect some different usb ports to you motherboard just to rule it out,if you have a motherboard box laying around there should be a few in there.

 

hmm ill have to play around with it. Yes i hadn't even connected the usb, it just touched it. When it cuts out it cuts out so fast that it's hard to believe it's a driver problem because that would at least take a second to load. I'll pull off the usb ports and have a look but i don't have anything to exchange them with at the moment.
*EQL*

 

Have you tried wiggling your VGA cable see if the video cuts?Made sure its screwed in tight?

Probably silly question,I'm scraping the bottom of the barrel:-D

 

yup. Im using DVI to HDMI, but yes, i've tried that AND ive tried switching to VGA.
Anyway, let's see if it happens again. I've pulled off the USB and didn't see anything. Checked the cable and nothing, but I tried changing which USB header it's plugged into. Perhaps that will make the difference.
*EQL*

 

Ok, so it happened again today.
Any ideas?? I'm tempted to just unplug the front ports and buy a usb hub :S.. maybe i should contact the case manufacturer and complain...
*EQL*