Product Family: Act!
Product: Act! Pro, Act! Premium, Act! Premium (access via web)
Version: 2005 and later
The number of contacts and performance depends on a number of factors including system resources and limitations set forth by what version of Microsoft SQL Server (Express vs Standard) you are using as Microsoft SQL Server Express has a database size limitation of 10GB. Your hardware configuration, hard drive storage limitations, memory, and processor speed also play a role in the number of contacts and performance of the database. If you are sharing a database, additional factors include the speed of the network and the number of users sharing the database.
Generally speaking you can expect reduced performance if a database contains more than 40-50,000 contacts and/or has 20 or more users. The more RAM and processor power available, the more flexibility you have maintaining a larger database.
In addition, there may be other factors which can slow performance at this level of usage. There have been Act! users who have as many as 300,000 (or more) contacts in their Act! database. However, for database sizes larger than around 40-50,000 contacts, it is recommended that an ACC be consulted to maintain database integrity and efficiency.