eTeknix published AMD Confirms USB Problems with 500-Series Motherboards
A quote from the article:
Following the launch of the AMD 500-series motherboards, there has been something of a relatively quiet but consistent complaint from a number of users. Namely, for reasons unclear, some USB devices utilizing the platform would randomly disconnect. Something that would clearly represent a very vexatious problem.AMD Confirms USB Problems with 500-Series Motherboards