I decided to try changing the cluster size on an internal 1 TB NTFS drive from 512 to 4096. The drive was about 1/3 full, single partition. Partition Manager 10 has been running for *6 days* so far, and I have no idea when it might finish. It's modifying the cluster size on disk. It's running in standalone boot mode. It occasionally changes the Time Worked and Time to Finish to seemingly random numbers, since they go up and down and bear no relation to anything. I'm pretty sure it's not hung because the disk light is solidly on, but I can occasionally hear it seeking. I'm afraid that if the power goes out, or something else happens, that it will leave the disk scrogged completely. And I would like to have the computer back at some point. Has anyone changed the cluster size on a 1TB drive with data on it, and could tell me how long it took? Would stopping PM leave the partition unusable?