If you try to use Power BI Desktop to create a dashboard, Power BI imposes a hard limit of 250 MB as the maximum file size. In my scenario, I had several 500 MB csv files that I used to create a dashboard. Power BI Desktop works fine but when you try and publish to Power BI you are stopped because the Power BI Desktop file is more than 250 MB.
I tried moving the files to Azure Blob Storage but that won’t work either because when you run the query to load up the files, it downloads the content back into your local Power BI Desktop file.
The only way around the limit seems to be to use a data source that queries in real time (“Live with direct query”) instead of being cached through Power BI Desktop. The options currently are Azure SQL, Analysis Services Tabular databases on premise, Microsoft Stream Analytics, SQL Azure Data Warehouse or Spark on HDInsight. However, the ONLY option for a live connection in Power BI Desktop is SSAS and most recently in preview SQL Server and Azure SQL.