You might also want to run Crystal DiskInfo on all the drives to see if any SMART errors are showing up. This may identify if any drives are in trouble (and which ones).
And if you haven't yet, back up everything important. You may be on borrowed time with at least one disk.
Main System: i7-8700K, ASUS ROG STRIX Z370-E, 16 GB DDR4 3200 RAM, ASUS 6800XT, 1 TB WD_Black SN750, Corsair 550D
HTPC: I5-4460, ASUS H97M-E, 8 GB RAM, GTX 970, CRUCIAL 256GB MX100, SILVERSTONE GD09B