Question A front USB port is broken, and my entire PC won't start up

[hoover815]

Hello,

Last night, I plugged in a USB device in one of the front ports on the NZXT H500. I did not hear an audio notification that plays on Windows 10 devices when a USB device is connected. I unplugged the device only to find that on the USB cable itself was the purple receptacle in the port.

https://imgur.com/58Yafej

View: https://imgur.com/58Yafej

After realizing this, I noticed my computer was frozen. I shut my computer off, and since that night my PC hasn't been able to turn on when I hit the power button.

All that happens when I press the power button is that the fans in the PC start to spin and the orange light on my motherboard turns on for just a second, but then everything turns off. This will keep repeating until I hold down the power button again. Sometimes, the orange light comes back on and the fans start to spin again for a bit longer, but then they stop shortly after. My motherboard is the GIGABYTE B360M DS3H, and my PSU is the EVGA 100-W1-0500-KR 500 W1.

My current theory is that power is being distributed to the front I/O panel, but since one of the USB ports doesn't work, my PC can't start up as a result. I've had no problems with power or startup until the USB port broke. I have tried to disconnect the cable that connects to the USB 3.0 slot on my motherboard, but nothing changes. There isn't a USB 2.0 connector connected to my motherboard either. I have also not found any other way for me to disconnect or disable the USB slots on the front I/O panel without starting up my PC. Is there anyway to fix the issue?
Thank you for your help.

 

[velocityg4]

Leave the front USB ports disconnected from the motherboard header. Unplug the computer from power. Hold the power button for ten seconds and leave unplugged for ten minutes. You may as well remove the motherboard battery and do a CMOS reset during this time. Plug it back in to power and hope the reset worked. Leave the front panel unplugged.

 

[hoover815]

I contacted NZXT customer support and they said they would ship me a replacement front panel module since I still have warranty (includes the USB ports, audio ports, and power button.) I might just wait until that arrives, and hopefully installing that will fix my issue.

I am curious regarding velocityg4's solution, though. From my understanding, holding the power button down serves to discharge voltage in the motherboard and resets some BIOS settings? Is it necessary to remove the motherboard battery and reset the CMOS or is it just for good measure?

Having a replaced front panel would just be more convenient overall I think. but I appreciate the help regardless.

 

[velocityg4]

A CMOS reset is just a normal diagnostic step on motherboards which fail to POST. As it resets the BIOS to factory settings. In case the settings are corrupted.

Typically this is a procedure which requires removing the battery. Then moving the clr CMOS jumper. You do not want to move the jumper with the clock battery in nor connected to power. Also you'll want to return the jumper back to its original position before placing the battery back or connecting to power.

Some motherboards have a button for this.

 

[hoover815]

Thanks for the followup. This morning I tried to just hold power for 10 seconds while my computer was unplugged from power and let it sit for 10 mins, but that didn't work. I then tried to clear the CMOS; there is no jumper cap for my motherboard so I just referred to my motherboard manual and touched the two "clear CMOS" pins with a screwdriver for around 5-10 seconds. Doing that alone didn't start my pc, and doing that in combination with holding power and letting my PC sit didn't work either. The front USB ports were disconnected from the motherboard in all of these attempts.
The result is the same as before - orange light, fans start to spin for a bit, then everything turns off and on repeatedly until I hold power again.

I haven't tried to remove the motherboard battery yet because the motherboard manual states to replace the battery with an equivalent if I want to successfully clear the CMOS. This makes me uncertain if taking the battery out and putting it back would achieve anything but it's probably better than nothing.

 

[hoover815]

So I've since tried the following and unfortunately:

1. removing the motherboard battery for around 30 minutes and then clearing the CMOS while the PC was unplugged (also held power down for 10 seconds and unplugged my PC before doing that)
2. running the PC with the SSD, hard drive, GPU, and a stick of ram disconnected from the motherboard as well as the PSU

its the same result of the orange light coming on for a second and fans start to spin before stopping and repeating until I hold down power again. Still the light and fans come back on for another second sometimes but shut off afterwards.

Feels like I've exhausted my options and it definitely seems like a motherboard issue if disconnecting the front USB cables and doing all the other steps hasn't worked. Guess I just have to get a new motherboard?