> 
> Depends on the device. The problem is that some IDE controllers don't have
> large enouth FIFO, so it may grab the PCI bus (thus preventing other devices
> from using it) but not transfering data. Yes, with a poolry-designed SCSI
> controller you'll have the same problem. With a good IDE or SCSI controller
> you don't have this problem.

could you tell me manufacturer of GOOD ide controller that don't have such
problems.
> It's just that there may be more bad IDE than SCSI controllers around :)
> >  And as an aside, lots of newer IDE controllers don't rely on the CPU
> > nearley as much as old implimentations did.
> 
> This didn't change much over time: all IDE controllers relies on the same IDE
> DMA spec. Some of them may need extra reg read/write to ask interrupt, or
> check interrupt status but this doesn't count that much.
>