Strange issue with Asrock B550 Taichi - USB 3.0 port doesn't recognize USB 2.0 devices

dvader

Adept
Hi,

Just wanted to share a strange issue I just noticed with my build.

Mobo: Asrock B550 Taichi
Proc: 5600x
Ram: Teamgroup TForce 3200 8Gx4
BIOS: Latest stable 3.2
No overclock just base values.

The system works just fine however, I recently tried to plug in an old USB 2.0 pen drive in the front USB 3.0 header and it wasn't recognized. Troubleshooting further no USB 2.0 device is working for that matter (not even mouse and keyboard), I plugged in a USB 3.0 pen drive and it works just fine. Does anyone have any clue as to what is happening? The motherboard is still under warranty though in case I need to RMA it.
 
Some bios has option to force only usb 3 on front-header or usb channels. Check if thats there and is enabled. Set it to auto or disabled.
 
check device manager, if you see any unknown devices when usb 2 devices are connected its probably a driver installation error, reinstall chipset drivers
 
Some bios has option to force only usb 3 on front-header or usb channels. Check if thats there and is enabled. Set it to auto or disabled.
Asrock does have this option but it's already set to 3.0

and I have unplugged any/all USB devices. Just keyboard and mouse.
check device manager, if you see any unknown devices when usb 2 devices are connected its probably a driver installation error, reinstall chipset drivers
No unrecognised devices. Unplugged everthing except keyboard and mouse
 
Last edited:
Pull out the USB3 connector and see if any of the pins are squished on the motherboard. Its a notoriously bad connector and things like that tend to happen with it.
 
Update: I had a USB header splitter which was used in the past to debug something,

One of these..... And everything works with this so seems like not a motherboard issue (even if I RMA it, it's just gonna be sent back anyway). Now I have two cabinets of the same model (long story) so I switched the front panel and still the same issue and this front panel works with another system without any issues. Now I am dying of curiosity as to why this is happening. Since this is my main system and I need those ports I will just get one of those cables with ports on the PCI slot, but again what the hell is happening....

usb3header.jpg

Pull out the USB3 connector and see if any of the pins are squished on the motherboard. Its a notoriously bad connector and things like that tend to happen with it.
Yeah tried that and as far as human eyes can see, the PIN looks fine.
 
Wow, I'm stumped. Does the USB2 pendrive work in both ports of your tester?
Yup everything works on both ports, I tried every possible USB device but everything works. I called support and they agreed to ship me the front-panel USB ports without any fuss. However, I am still stumped what the hell is happening?

The only possible explanation I have come up with is that one of the 4 pins for USB 2.0 in the port has gone loose. Since USB 3.0 can work as long as it gets 5v from the top 4 and the bottom 5 take care of the rest; this would explain everything, I have a few USB ports/cables lying around, and I will break 1 of the top 4 pins and confirm if USB 3 work even if few PINs have gone wrong.

Update: Yup I broke the D+ and D- Pins (the middle two pins) and as it should USB 3.0 pen drive still worked but 2.0 failed. Since the panel is installed vertically and during the debugging, I plugged the pen drive while holding the panel horizontally the middle two pins made contact, and the 2.0 got recognized while troubleshooting. As it turns out if I hold a USB 2.0 drive at a certain angle it works.

I have edited the thread title in case someone stumbles upon a similar issue.

Let's see how long it takes to get the front panel for the cabinet.

I broke 3 USB cables for science :D
 
Last edited:
Back
Top