There is actually very little differance in performance between the same make/model and with ATA/SATA
This is because at present the older 100/133 bus is still plenty wide enough to not restrict even the fastest of drives at maximum bust rate, the older bus is not restricting (bottlenecking) data flow.
Obviously though, as drives get faster and research and developement money is aimed squarely at the newer SATA150 interface, the SATA drives will gradually pull away.
All mainstream motherboards to date, that support SATA also have the normal IDE connections as well and drives can also be mixed in the same machine.
If you have a choice, then go SATA, the differance in price is minimal nowadays and the very slight performance edge and cleaner wiring are worth the few dollars extra spent.
But if you havn't got SATA connections, then don't beat yourself up over it! you aren't loosing out on much.
Martin
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