I bought a Seagate 320 GB SATA internal hard drive and it worked fine for about 2-3 weeks, then one day my computer stopped seeing it. it doesn't show up anywhere on my computer, not in the device manager, disk management or the bios. I'm running Windows XP w/the sp2. Other than that, my computer runs completely fine. Any help would be greatly appriciated. Thanx.
Open up your case and make sure all cables are connected. In my computer at least, the power and SATA cables have a tendency to get knocked out easier then IDE ones. If they are plugged in, and still no-go, put the drive in another computer... just to see if it works.
Unfortunately this is going to be almost certainly a dead drive if none of the above tips work.
SATA drives often have jumpers to allow you to select SATA 1,5Gbps or 3,0Gbps operation (SATA/150 and SATA/300). Normally SATA/300 would be backwards-compatible. But in some combinations this does not work properly, and unless a 1,5Gbps jumper is set on the SATA drive the system would not recognise it.
This only applies to older systems with 1,5Gbps SATA ports while connecting a newer 3,0Gbps SATA harddrive.