> Yes, the CPU has to touch almost all the data on a IDE bus, while > SCSI controllers off-load much of the processing from the CPU.
That's no longer true and hasn't been since the advent of "Mode 4 PIO" drives in about 1996. These are driven by DMA and can sustain quite high transfer rates with low CPU loading - but only if driven by an appropriate device driver. In the early days of this tech, many implementations were extremely buggy, so Windows is very cautious when enabling DMA. Most Windows machines more than a couple of years old won't enable it automatically. Linux was bolder but hit problems on some hardware. I don't know what OS X does, but I doubt it uses PIO... Mind, the ATAPI API is much more basic than SCSI - no asynch xfers, no disconnect etc. SCSI can still do much more. -- Liam Proven � http://welcome.to/liamsweb -- Unsupported OS X is sponsored by <http://lowendmac.com/> Support Low End Mac <http://lowendmac.com/lists/support.html> Unsupported OS X list info <http://lowendmac.com/lists/unsupported.html> --> AOL users, remove "mailto:"; Send list messages to: <mailto:[EMAIL PROTECTED]> To unsubscribe, email: <mailto:[EMAIL PROTECTED]> For digest mode, email: <mailto:[EMAIL PROTECTED]> Subscription questions: <mailto:[EMAIL PROTECTED]> Archive <http://www.mail-archive.com/unsupportedosx%40mail.maclaunch.com/> Using a Mac? Free email & more at Applelinks! http://www.applelinks.com
