Enabling dynamic tab rendering in Conga Grid improves performance for grids that are made up of multiple tabs in a single Visualforce page. 

Once this feature is enabled it will only apply to Multi-Tabular Grids created after the feature was enabled. 

To enable Dynamic Grid Rendering

  1. From within Conga Grid, click Conga Grid Setup

  2. Click Global Defaults

  3. Under the Dynamic Tab Rendering section, click Enable or Disable