Hello Group, Background ========== On of our current SQL 2000 servers encounter HDD (I/O) bottlenecks when it gets busy so we plan on upgrading it. The SQL server is being used to generate dynamic web content and all the queries are well tuned and tables indexed. However, when we get in excess of 500 transactions per second (1 transaction for each web visitor) then the web servers, which are connecting to the SQL server, being to queue requests. In order to resolve this we will upgrade the SQL server. Question ======== Is there some mathematical formula we can use to calculate the I/O capacity required in the new SQL server to reach 1,000 transactions per second? So far we have been advised to get 6 scsi drives which are 15,000 rpm. We will put them on 2 RAID controllers, 4 drives for OS with RAID 5 and 2 drives for Log files with RAID 0. Does anybody have a better suggestion? Thanks in advance.