I just want to clarify, you're looking to setup table partitioning within the schema of the database to multiple filegroups, correct?

> Yes I am trying to Partition my table, here. with multiple file group and multiple files.

Ex: USD will have USD_FG and USD_FILE.ndf file

The reason I'm trying to clarify is because I've never seen an estimate for storage before, are you using a wizard?

> Yes I was using Partition based on Wizard

Additionally, is there an index on the field you're looking to partition across? I'm wondering if the statistics are just wildly off. If there's an index on that field, UPDATE STATISTICS WITH FULLSCAN the table and see what kind of estimates you get.

> No Indexed are on the table

Finally, and I hope you're on a dev system, just chuck the estimates out and do your partition. Then go to the dm_ views and check your partition sizes with actuals. Estimates are notorious for being wrong.

> Yes Im on a test DB, I will Test it.