Users have been reporting that the latest AMD graphics driver, Radeon Software Crimson Edition, has been incorrectly setting fan speeds. Some users report that the driver spins up fans to 100% and others report that they slow down to 30% regardless of load.
Over the weekend, AMD acknowledged the issue and claim that a fix is intended for Monday.
Some users also claim that the card will stick with that fan setting until it cooks itself. This seems odd to me, since GPUs (and CPUs of course) are now designed to down-volt if temperatures reach unsafe levels, and even cut power entirely if heat cannot be managed. We haven't really seen reports of graphics cards cooking themselves since the Radeon HD 5000 series implemented hardware in response to Furmark and OCCT. That said, the driver bug might some how override these hardware protections.
In the mean time, you'll either want to keep an eye on your fan settings and reset them as necessary, or roll back to the previous driver. AMD didn't comment on the high fan speed issue that some were complaining about, so I'm not sure if this fix will address both issues.