Question Reboot Issue - Loose USB 3.1 Cable?

[xHanck]

Hi all,

In recent months I've been having an issue where my PC reboots should it get knocked ever so slightly. I just sort of deal with this as I don't really have the time to set aside troubleshooting and it isn't a major issue as I rarely knock it. However I've just returned home from uni for the holidays, and after the car journey home my PC just wouldn't boot, I've had this issue before, so I just re-seated a few things as I normally would (CPU power, RAM, GPU) however noticed the USB 3.1 connection to my motherboard was extremely loose when I went to reseat it. It is still really loose after I plugged it in again, I think the clip has snapped off it.

Could the poor USB connection be causing my PC to reboot? All the other connections are solid so I doubt a small knock would cause my PC to reboot, this USB cable is the only one that could (clearly) be affected.

 

[vertigo_2_20]

You could simply unplug it and see if the problem goes away, but it seems unlikely. My first thought was actually that it might be a loose connection or short in the wires that connect the power/reset buttons to the motherboard. Also, does it actually reboot or does it power off and you have to power it back on? Does Windows shut down properly, or does it just suddenly lose power and the computer dies?

 

[xHanck]

You could simply unplug it and see if the problem goes away, but it seems unlikely. My first thought was actually that it might be a loose connection or short in the wires that connect the power/reset buttons to the motherboard. Also, does it actually reboot or does it power off and you have to power it back on? Does Windows shut down properly, or does it just suddenly lose power and the computer dies?

Thanks for the reply. It definitely isn't the USB cable, I wiggled it sufficiently whilst the PC was on and it didn't reboot.

To answer your question, windows definitely doesn't shut down properly, the PC just dies and then boots again like a second later. I think my issue is the top-right mounting screw for my motherboard. Its screwed down as far as it will go but doesn't make contact with the mobo, so it doesn't sit tight on that corner and can move along the screw.

 

[vertigo_2_20]

A loose standoff connection shouldn't cause this. Try disconnecting the wiring for the front I/O from the motherboard, at least the ones for the reset button, since that's the one that's likely causing this if it is that. Since it's not shutting down, it wouldn't be the ones for the power button, and leaving that connected will make it easier to turn the computer on and off, though if it still happens you should probably disconnect that as well and turn it on by carefully jumping the pins (or making your own wire and switch to connect to just those pins). Also check the power connections, specifically to the motherboard (and the PSU if modular), but if those were the issue I'm not sure it would boot back up on its own.