OK, I'm just one week away of doing the real thing, so I'm going to review the process. It's the continuation of this thread but my last post was ignored, so I will start with a clean sheet now. I will use one SSD on MBR (UEFI on BIOS mode) with 2 partitions, XP on first, and 7 on second partition (that is, no 100Mb partition from 7). This is what I want: on XP: C: (SSD 1st partition) D: (2nd Drive) (for "Documents and Settings") on 7: C: (SSD 2nd Partition) D: (2nd Drive) (for "Documents and Settings") M: (SSD 1st Partition) I need 7 to watch XP partition for the SSD Trim, which XP can't