Updated on July 22, 2020
Dell Opitplex 755 Low Voltage Issue
I put this short video together for an end user about a year ago, and since then several people have found it via YouTube… When the BIOS battery on the Dell Optiplex machines goes dead, the type of SATA operation goes back to default. This will likely break your machine, although strangely it will begin to boot windows before moving into a spiral of death. The BIOS reverts to AHCI and needs to be moved back to ATA… keep in mind that you’ll loose this setting every time you turn the machine off, until you’ve replaced the motherboard BIOS battery… but this will keep you up and going while you track one down.