The Optiplex GX270 is a heritage PATA motherboard system - it is hard wired to PATA drives and cannot boot from SATA. However, it does have a SATA port hidden away inside the case, but for why? Perhaps it was just an experiment when the ealiest SATA technology became available? I estimate that plugging a SATA drive into that port would prompt the 270 to see it as an auxiliary drive. I am pretty sure the 270 C drive is on master jumpers, so the computer shouldn't get in a muddle as to which drive to boot from?
Thanks.