Les Mikesell wrote:
But it is just a match for the Seagate drives with the default layout using one partition that fills the disk. If I have to skip some amount at the start of the partition I think that will make the partition size not match, making it impossible to add as a raid member.
750GB drives can vary quite a bit in size +/- depending on the exact model. The required trim is 0-3.5K, and its due to the MBR on the first "track" of the drive before the first/primary partition starts.