I'm going to be upgrading the hard drive on an old-model Mac, but before I make a purchase, I want to research my options. At this point, I know for certain that the computer's drive interface is ATA-2 and that I will need to buy a drive that has a PATA, not SATA, interface. What I'm not certain about is whether or a modern drive would be sufficiently compatible with such an old interface.
I do have a background in both electronics and programming, so I could do detailed research about the differences between ATA standards, but I thought I would see if anyone out there has enough (accurate) knowledge to address my questions, thereby allowing me to avoid engaging in more in-depth research.
So here are my questions:
Are all PATA standards backward compatible?
In other words, if I buy a drive that complies with an ATA-4, -5, -6, -7, or -8 standard can I plug it into an ATA-2 interface and expect the drive to function?
If there are any incompatibilities among the different generations of ATA standards, are they merely speed-limiting issues or are there differences in the functionality of the pins that might cause permanent damage to the drive or the computer?
For that matter, since drives tend to be sold independently of computer systems, are there any PATA variations that I should watch out for (that might have manufacturer-specific pin configurations)?
I've noticed that some sellers are listing drives with the tag “PATA II”. Does anyone know exactly what the “II” refers to? Does that mean it's ATA-2 compliant, or is it some other marketing designation that some manufacturer concocted?