Some USB devices randomly stop working

[Jonsi]

Over the past few weeks I've had a problem where my keyboard has just randomly stopped working, lights go out and then nothing happens when I press buttons. Seems to happen completely at random and not be triggered by any action on my part. The only way to fix this is to shut down the pc and then starting it, simply restarting doesn't work as I'll get to. 

 

I couldn't find any threads with the same problem and after much testing I couldn't even narrow it down to any component, if it was the keyboard or even if it was software related. However just now a USB stick lost connection in the exact same way and at the same time as the keyboard so it seems to strongly point towards something USB related. However only certain USB devices seems to be affected by this, my mouse and headphones wireless adapter have worked fine at all times even when the keyboard was dead. The keyboard does have a built-in USB hub which I suspect is the reason as to why it is affected while other stuff, including other keyboards, are not. 

 

I've been noticing strange things when restarting as well. If I restart through Windows after the keyboard has died I get a "black screen 99" error which seems to be some motherboard I/O failure or completely dead motherboard. Most of these posts however are about new builds where the pc doesn't even boot, for me it only happens after restarting when the keyboard is no longer working. The most common consensus on this is that the motherboard is just dead but mine is obviously not. I've tried the suggested fixes anyway but nothing worked. The only way out of this 99 error is to shut down completely or use the reset button. If I use the reset button I will boot into Windows normally but the keyboard still won't work and I will have to shut down the pc completely before powering up again. After shutting down completely the keyboard always works again without any problems.

Using the case restart button after the keyboard dies works the same but the black screen error says 9c instead which seems to be pointing towards something USB related again. A lot of posts say that it is boot order related but I've checked the settings and everything seems fine and none of the suggested fixes worked either.

Restarting before keyboard failure works just as it should with no problems at all so they seem to be related. 

 

 

A list of earlier attempted fixes: changed the keyboards USB cable (A to C), tried several other USB ports on various parts of the case, tried to see if I was doing anything particular when it was disconnecting, reinstalled/updated a bunch of drivers, removed all overclocks and reset Bios settings to default, ran virus checks, unplugged all extra USB ports from the motherboard, uninstalled all USB devices and the keyboard from device manager and reinstalled, made sure no power saving stuff was active, wiped keyboards on-board memory settings, repaired pc registry, did a DISM scan and finally reinstalled Windows. I have left the pc on for about 12 hours hours in safe mode without any problems although since it happens so randomly I can't quite be sure it won't happen if left longer. I've tried my mk850 keyboard on another PC and an old dell keyboard on my PC and they've worked perfectly. Using the dell keyboard on my pc even worked while my main keyboard had died and was still connected and unusable. 

 

It seems to me like my motherboard is dead or dying but this is about where my pc knowledge ends so I could be wrong. Any idea what's going on or how to fix it if it even is fixable would be much appreciated. 

 

 

 

 

Windows 10 home 64bit 

Crucial M500 240GB SSD (OS) 

Seagate Barracuda 1TB

Seagate Barracuda 2TB
Cooler master mk850 keyboard
Logitech G400s mouse
Msi Z87-g45 motherboard on BIOS Version 1.9
Intel I7 4770k @3.5GHz
2x8Gb Kingston HyperX fury ddr3 @1333MHz ram
Asus ROG strix GTX 1070

Cooler master G750m 750w PSU 

[Juniosaint]

I'm having the same problem on my relatively new computer. My wireless mouse/keybord and my bluetooth dongle just stops working randomly. It seems that it happens based on the usb ports it is connected to. The front panel ports (which are 3.1 gen 1 with 3.0 case wiring) and the backpane usb 2.0 and 3.1 gen 2 are all having this problem while the usb 3.1 gen 1 from the backpane works always without a problem. When I have this issue, in addition to solving it shutting down I can generally just switch the dongles from the keybord and bluetooth to the ports unaffected and it works, after a while the affected usb ports starts working without the need to reboot.

 

My rig:

AsRock b450m Steel Legend P3.9 bios version

Ryzen 5 3600x

4x8GB of XPG DDR4 3200Mhz memmory

Asus Dual RTX 3070

Wireless mouse and keybord KM636

Generic USB dongle

Corsair VS500 PSU

SSD XPG S40 500gb NVME