Our performance tip is about placing a paging or swap file on a RAID drive. The location of the paging or swap file can cause severe delays in performance, if you allocated the paging file on the same physical disk as the OS and the system starts paging, the I/O will increase and everything will slow down.
A common mistake is that RAID 1 will optimize performance and yes, this is correct, but if you place the paging file on the drive with a RAID allocation it will slow down performance.
Why? A paging file is not needed if the drive fails because the OS can allocate a new one. A paging file is written sequential and not randomized; this will slow down performance.