The config file /etc/sysconfig/harddisks assumes that the disks used on the system are homegenus. I have 3 different disks, one new and supports all the lates bells and whistles as UDMA/66, the other much older. They need very different hdparm config. I also have a motherboard with some DMA bugs so I must f.x. turn of DMA support for my CD-R/RW drive but I must turn on by hand the DMA support for my new IBM disk. In future releases, make it possible to use different settings for different disks.