Computer locks up hooking up usb cable

My computer locks up when I hook up the USB A to USB B cable. It won't go past the bios screen. Any body seen this before? It worked for a week and a half before it started this.

2/10 - Tried another device on the same USB cable and it works fine. So, this would make the issue a problem with the N5200.

Not sure what it means... After sending my conf.bin to David Jaw at Thecus, he has confirmed a problem of having the USB hooked up during boot will cause some computers not to boot up. I don't know if I need to be happy or sad. :)