SSD Optimizing Guide - Standard Optimizations - NTFS 8.3 Name Creation
The creation of 8.3 filenames and directories for all long filenames and directories on NTFS partitions may decrease directory enumeration performance. An 8.3-compliant file name refers to MS-DOS file-naming conventions. These conventions restrict file names to eight characters and restrict optional extensions to three characters.
This is required to be enabled if you need to run older 16bit applications/MSDOS.