I had temporarily taken out the SSD which is the primary drive to a PC. When I put it back in the computer wouldn't start and gave errors like "disk read error" or "no bootable media found". After trying various things, I found the problem was that a different port on the jumper cable connecting it to the power supply needed to be used? Is there something special about the particular port on the jumper cable? Out of curiousity I changed the port on the jumper cable that the secondary hard drive used and it didn't make a difference and it still was detected.
This was like the problem where it said the CPU was over heating because one outlet was specially designed for CPU fan.
If relevant the power cable was SATA and the SSD was connected by SATA-3.