My computer started freezing about 3 days ago and it caused the primary OS to become corrupt. As a result, I reinstalled windows on a different harddrive but I'm still getting freezes. I believe the issue is somehow disk related but it isn't the harddrive itself as they're different harddrives. The one I'm using right now is almost new. In the system event log I see "error 51" repeated frequently along with other disk related issues. It for example complains about the driver "nvraid" which I was using previously as I had a raid prior to the problems. I've since moved all the data to other drives and dissolved the raid into two harddrives. Would windows even need this driver now? The lock ups occur most frequently when I'm transferring a lot of files around. It happened several times when I was moving the data around prior to dissolving the raid array. What I'm looking for here is stability... some websites I was looking at suggested that I change the prefetch value in the registry to "0"... currently it's "3" (Default setting on this system as it's freshly installed). I've attached my event log for examination... as an aside that isn't my name in the log... I make a point of using fake names and aliases whenever the computer asks for my name unless it's absolutely required that it be accurate... which is just about never. Anyway, my system disk is plugged into the 4th SATA plug on the motherboard now... would that cause problems? Should it be in the first plug? The OS boots fine seems to generally work very well except for when it freezes. You can see how frequent those times are from the event log. Every time error 51 repeats about 20 times in a row that's a freeze.