I know this is technically not a fedora question, but I'm hoping to leverage on the collective smarts here.

I recently received a Sandisk Cruzer 16GB. I successfully removed all the U3 crap.

However, after converting the fs type to ext3, GParted displays a used space of around 900MB. df displays a different amount and qtparted displays yet another amount. Converting back to fat32 in GParted displays 15MB of usage whereas converting in Windows displays 8kB usage.

With ext4, GParted displays a used amount of ~450MB.

The total size is mostly correct with regards to Sandisk's 16GB actually being 16billion byes. What is a new filesystem displaying false used space readings? What is happening?