I would like to replace four aging physical servers with one virtual server. What is the best way to insure the VM server is sized correctly? The requirements of the apps that will be running on the four servers are APPLICATION SERVERS - QTY 3 - These will run the application layer for the web server, Business Objects Business Intelligence app, and various other small client server apps. The three most heavy hitting apps each have the following server requirements. So, if I bought three physical servers, this would be the requirements for each of them Processor - Dual 2.83 GHZ (or faster) Ram - 4 GB Raid 5 - 50-100GB usable space NIC - 1 GB Web Server - this will run one asp.net e-business app that will talk to our dedicated SQL server and the three app servers above. The E-Business software has these requirements for the web server Processor - Quad 2.83 GHZ (or faster) Ram - 8 GB Raid 5 - 50-100GB usable space NIC - 1 GB What is the best tool to determine what I need from a hardware standpoing in a virtual server? I am planning on using VMWare.