It is the size of the file. Look in the cp for inline images
If the file is larger than the setting it becomes a link
From memory try primary settings.
Okay I looked it up.
Control Panel » Display Options General-tab- primary
[-] Topic Display Options
Max Size for inline uploaded images
If an image is attached to the post, if it is smaller than the specified size (in bytes) it will be displayed in the post.
Last edited by Ruben; 08/16/2012 4:42 PM. Reason: Added comment