IDE performance 2.4.18 slower than MSDOS

These are for an unmounted Seagate 80GB IDE Primary ST380021A DMA in a Celeron 466, Intel 815BN, 256MB.

dd 4.0.36  linux-2.4.18--------
MB/s       Input  Output Hdparm
DOS        42.10      ?  -Tt
/dev/hda   36.36  19.94   37.21

/dev/raw 2.86 3.28 98.46

Linux 2.4.18

time dd if=/dev/hda of=/dev/nul
301.6user 1093system 36:41.05elapsed 63%cpu
36.36MB/s

time dd if=/dev/raw/raw80 of=/dev/nul
690.95user 5060.35system 7:31:39elapsed 21%cpu
(IDE light dim)
2.86MB/s

time dd if=/dev/zero of=/dev/raw/raw80
626.32user 7570.34system 6:46:39elapsed 33%cpu
(IDE light dim)
3.28MB/s

time dd if=/dev/zero of=/dev/hda
304.34user 1413system 1:06:54elapsed 42%cpu
(IDE light medium 123456, IDE light off 789)repeats throughtout 19.94MB/s