My xHCI USB 3.0 Controller no longer works, and I have no idea why.

I've been trying to troubleshoot this for literal weeks, and I cannot for the life of me figure it out.

I'm running Windows 10 on a Gigabyte Z97X-Gaming 3 and i7-4790. It has six USB 3.0 ports and four 2.0 ports on the back I/O, in addition to the two 3.0 ports on my case I/O. A few months ago I began to notice that when I would plug something in, Windows would give me a "USB device not recognized" notification, but that would usually fix itself when I replug. Sometimes it would give me the error and continue to work like normal, after a few disconnect/reconnect sounds.

Then I began to notice my keyboard wouldn't work when plugged in some ports. Weird, but I chalked it up to the cable or something (it wasn't). *Then* my USB microphone started to give out a really distorted and cut-out signal, which would be fixed for a few seconds when I replug, and I would get the Windows "not recognized/malfunctioned" error again. After days of troubleshooting the microphone problem, I bought an entirely new microphone thinking that it was the problem (again, it wasn't).

That's when I realized something was wrong with my 3.0 controller. I researched this, and after a few days **here's what I've tried doing:**

- **Reinstall Intel USB 3.0 eXtensible Host Controller drivers** - I found links everywhere for this, but when I run the setup it says that the driver doesn't apply to my computer, even when I download the driver straight from the motherboard support page.

- **Install modified versions of the Intel driver** - After days of digging I figured out how to modify the driver so that the setup program would actually run and install. This didn't fix anything.

- **Turn off xHCI in my BIOS** - This technically *did* work, but it made all of my USB ports 2.0 speed, which isn't gonna cut it for me. I have devices that I use frequently that require 3.0 speeds.

- **Reinstall Windows** - You'd think this would do something, but nah. Nothing.

- **Use "Auto" or "Smart Auto" for xHCI mode, disabling xHCI handoff in BIOS** - None of these options seem to do affect anything at all.

I feel like I've hit a dead end here. When xHCI is enabled, half of my USB ports don't work, and the ones that do are all 2.0 speed. I'm completely unable to use things like my VR headset, which requires a 3.0 port. What should I do here? Do I just have to cut my losses and upgrade my motherboard?