Thread: How to reduce the size of a gmapsupp.img file on a card???

I absolutely agree with that excellent explanation osiris4isis, thanks for that. As well as the capacity variance between manufacturers, any individual drive which experiences bad blocks will have it's effective space reduced upon format because they will be 'locked out' as you've said. Additionally, even cards branded the same may vary a little in available space because some brands are 'fabless' manufacturers meaning they source batches of product from different factories.

Edit: The only truly non-confusing way for most ppl to converse about drive size is to use bytes. Inconveniently that means talking in 'rifle numbers'. If only MS would go the path of Mac and Linux and use the decimal factor for GB the mists would clear for many casual PC users.