Hey guys I have an old p2 300 machine, with an aopen MB that supports ATA/33. I am shopping around for a new hard drive, but I only seem to find ata/66 or ata/100, my question is are all the ATAs compatible, if I were to buy a ATA/100 for example would it work on my computer?? thanks.
Yes, the newer drives (and the cables) are backwards compatible, and will run at the older, lower bandwidth and speed settings. That would happen automatically with an ATA/66 or ATA/100 drive, simply by being on a regular 40 pin, 40 conductor cable.
The best thing you could do would be to purchase a relatively inexpensive ATA/100 controller card, and then connect the new drive. That will give you some upgrading ability, without having to change the mainboard, and the faster drive will give your system a nice performance boost.
The way I look at it ... if you are willing to consider the purchase of a larger, fast drive ... what's another $30-$35 dollars for a controller card? That will also give you another 4 IDE ports, which will allow for other, faster devices in the future.