When you create the database, you can decide how much the file should be increased. If you use the GUI the default is 10%. I have to admit that I don’t know how much the default is when you use create database statement and omit the part that tells how to increment each file. In any case this can also be modified and in my opinion it should be modified. If I have a database that is 500GB I wouldn’t want it to get 50GB in the middle of transaction. Most of the time I like to set my file growth to 200MB and monitor it so it wouldn’t get to the situation that it has to use automatic grow. In order to modify it you can run alter database statement (see more details in BOL) or use the GUI (right click on the database, select options from the popup menu and then use the files tab).

Adi