A devil in my PC

For the past 5 years I have been running a Asus P2B-F board with P3 450 and 1024 of ram plus a hard drive without any problems at all.3 months ago I purchased a Western digital caviar se and it is connected to the board via a Ultra100 TX2 raid controller. I good upgrade that ran also without problems until 2 weeks ago.Suddenly the disk crasches. It stops running. The cause, connectors on a small plate below the disk that connects the disk and the board on the disk burned.The data was retrieved, I got a new disk, the seller suggested a manufacurer failure. The same problem showed up again 3 times and we have given up trying to find out what is causing this. Raid controller and disk was tested on a different machine before installing it into mine again, all times apart from first time.Apart from this there are no problems with this machine at all. Has someone out there an idea what is causing a hard drive to crash like this, aparantly only on this machine, Asus P2B-F with the above hardware.Regard