5 boxing, one comp, slave clients randomly not responding

Everything is working fine, good framerates on all 5 windows, using HotKeyNet to open all instances, resize, remove bars and fill all space, and auto login. I can play normally, quest grind etc. Then occasionally one or sometimes two windows will go white, to unresponsive, and sometimes recoveres and im good as new. Usually I have to kill the process, and restart it. Any insight on this? It happens more often when zoning, such as the deeprun tram, or releasing spirit from corpse after a death. Those times all concide with HDD loading, so I figure something is up with the way the instances are writing to disk.

Here is my system specs.

Q6600 verclocked to 3.3ghz x4, 8gb ram, OS on raptor 10Krpm drive, slave clients on secondary 200gb HDD all in their own folders. I originally had all the slaves sharing a folder, but I had these problems, and made individual folders. Do I need to spread out to another HDD? I only have a 74gb raptor now, and was thinking about upgrading to a 150gb until the new velociraptor was announced, so I'm kinda waiting on that for my system drive. What should I do with the existing raptor? Buy another and raid them for the slave clients? Buy another and put 2 wows per drive, with the 5th being on the system velociraptor?

Or am I looking at the wrong place for this issue?

You're looking in the wrong place. ;) What video card are you running? When was the last time you upgraded your video drivers?

Im running an 8800gt 512 (g92) I got it about a month ago, and got the current drivers then. I am downloading the new drivers from last week now, hopefully it will help.

Once you get it all going with the new drivers, if that doesn't help, try going into task manager and setting the process priority on all the WoWs to LOW.