booting problem sony A690 laptop --no harddrive found

i have a problem with a Sony A690 laptop booting knoppix irq 5 idoes not respond on boot and i have an error message to that effect
it suggests trying the irqpoll option and says irq5 has been disabled -- the irqpoll option does not work. I suspect the harddrive is on a sata bus and using irq 5 . Where as knoppix will load it thinks there is no hard drvie and trys to use the DVD drive and mount it as hda -- which is bogus.
what is strange is that i have loaded kanotix on the exact same model vasio vgn A690 and have tried to use the kanotix cd that was used with
the same basic result -- irq5 disabled no harddrive found -- maybe a border line timing problem ? any advice would be welcome
rrk