What to do when your hard disk is dying and your SSD is sputtering
Problem: Hard Drive Disappears
Solution: If it’s a drive that was previously visible, the first step is to see if the drive shows up in the BIOS (check under Boot). If not, swap out the SATA and/or power cables.
If the drive shows up, run CHKDSK on it by right-clicking the drive in My Computer, choosing Properties, then the Tools tab, and then “Check now” and “Automatically fix file systems errors.” If the drive continues to give a ton of errors, and is behaving erratically but is visible in Windows, copy all data off it immediately if you can, or run Data Recovery on it STAT.
If the drive is not visible in Windows, your options are limited to the Freezer Trick (an hour or so of extreme cold sometimes sets things straight) or expensive forensic-style data recovery.
If this is a brand-new drive that’s not showing up, you need to initialize it first. Right-click My Computer and select Manage, then Disk Management and follow the prompts.