Partition Magic refuses to work on disk which have been partitioned by Linux fdisk.
All other Windows programs are happy with the partition table, including Boot Magic and Norton Disk Doctor.
Partition Magic should be smart enough to recognize that Cylinder/Head/Sector information is useless
because the disk partitions are larger than 8 GB.
My computer system is already six years old, but it has a 120 GB internal drive and 500 GB external drive.
The old (PowerQuest) version of Partition Magic worked fine on my computer.