[newbie] udm66

[Mandrake7]

hello i have some problems with my friends pc
when i install a linux distribution with kernel >= 2.2.17 when the kernel
finds my hard drives it enables UDMA66
if i install the new kernel and disable the UDMA when i start xwindow i
can't see anything to my screen the controller is Promise UltraDMA66
Any ideas??? thanks