AMD R9 M290x Not Detected

I recently bought an Alienware 17x with switchable graphics (Intel 4600 and AMD Radeon HD R9 M290x). It's been working like a charm until today, when it was suddenly unable to detect my AMD card. I've tried installing the newest drivers from both AMD and Dell - neither have worked. Many seem to have had similar problems when updating Windows 8.1, but I haven't updated Windows recently so I don't think that can be the cause. 

Any ideas?

EDIT: Solved not five minutes after posting this by updating the BIOS from the Dell driver and download site.