Also, if you don't want to get an additional card and only want to add a few extra GB of HD space, you can look at SCSI 20GB drives, and those will work without extra hardware. Or, if your Firewire card has an internal port, you can hook up an firewire/ATA bridge inside your case and use it that way. A raw firewire/ATA bridge can be found pretty cheap (cheaper than an ATA card), but you have to attach the drive yourself to the bridge when installing it.