I have been working on this issue for 2 weeks. The server is a dual quad opteron with 16 Gb ram. There are 4 VM's on the box and I believe I have nailed down the cause to the VM running SQL 2005. All four VM's are win 2003 std. The issue occurs over time as if the SQL slowly grinds it to a halt. Nothing really shows in the performance monitors on the VM or the host. Although, giving the VM more Ram to work with seems to delay the crash. The odd thing is the Host, while inaccessable, still seems to run the vm's in the background and I can remote into them. I have trend AV, all the latest patches and have scanned for malware. Anyone who might have an idea and needs more info just ask and I will supply the information.