INACCESSIBLE_BOOT_DEVICE on Alienware 17 R2

Hi,

    Started getting this error at startup. Replaced the hard drive with an 850 Evo SSD and loaded a fresh copy of Windows 10. Also updated to the latest version of the BIOS. This seemed to fix the problem, but now it's back again. Sometimes it boots straight away and sometimes I get the error. It is also getting UNEXPECTED_STORE_EXCEPTION BSODs. I checked the SMART info for the SSD and it shows over 16,000 communications errors between the laptop and SSD. Looking for suggestions on where to go from here - I'm out of ideas. Is the MB's disk controller hosed or is there something else I can try?