SharePoint Server 2010 Capacity Planning, Sizing Tool

These white papers and articles include information about the performance and capacity characteristics of the feature and how it was tested by Microsoft, including:

• Test farm characteristics
  
  
• Test results
  
  
• Recommendations
  
  
• Troubleshooting performance and scalability

Find all these stuff at : http://technet.microsoft.com/en-us/library/ff608068.aspx

The HP Sizer for Sharepoint 2010 is available for download at following link

http://h71019.www7.hp.com/activeanswers/Secure/548230-0-0-0-121.html