Non-System disk error after installing graphics card

If you are getting the following Non-System disk error after replacing or changing a graphics card:

“Error – Non-System disk or disk error. Replace and strike any key when ready.”

You may be experiencing a common problem.

If your system has a raid card, check to make sure all of the SATA cables are still tightly connected and make sure the RAID card is seated the PCI slot.

Or if you have an HP computer there is a known problem with certain Seagate disks that can be fixed by updating the disk firmware:

A common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools. ~ Douglas Adams