Originally Posted by mhm
do fdisk -l
then use the command dd if=/dev/zero of=/dev/hda5 bs=1024 count 1
assuming that /dev/hda5 is /boot, do it for other partitions, and google for dd command.
First of all, this is unnecessary. As we have already stated, you simply overwrite the existing Linux partition when you do the new install.
If you do use dd to erase a partition, the above command would only erase 1024 bytes. You have to set count in accord with the size of the partition.