I have a Windows Server 2008 machine that is resyncing disks after a powerloss. The issue is that the system becomes unresponsive after about 10 minutes. We've checked with resource monitor and found that the CPU's aren't maxed; but the disk I/O is well over 250MB/s.

We've attempted copying data from 1 disk to another; bypassing syncing of disks and this too causes the machine to freeze after about 10 minutes of copying data.

I have attempted to let the machine resync the disks for a few days with the machine on in this "frozen" state. By frozen I mean that NOTHING works on the machine, it's completely unresponsive; no mouse movement, etc.

I want to know how I would go about definitively checking if this is Disk I/O that is freezing the system. I know that disk I/O can freeze a system; but what can I use to run tests to be sure?