> > > interrupt. Also with today's IDE controllers you still have to read/write
> > > registers on the PCI bus, before and after each xfer. This is slower than
> > > main RAM, of course. With good SCSI controllers read/write of registers
> > 
> > yes - but this additional load isn't big unless you have one slow CPU and
> > 20 IDE drives. 
> 
> It's significant for a busy server - especially if it also has to deal with
> network interrupts.
but... wouldn't buying faster CPU be cheaper solution?