Firstly 500GB drives are never truly 500GB, HDD makers use the cheat that 1GB – 1000MB (The correct figure is 1024).
Secondly part of the HDD is reserved for the OS (epg cache for instance), another chunk is reserved for the fixed size file used for the time shift buffer.
If you take a brand new 500GB drive and format it in a PC you won’t get 500GB of storage capacity.
Firstly 500GB drives are never truly 500GB, HDD makers use the cheat that 1GB – 1000MB (The correct figure is 1024).
Secondly part of the HDD is reserved for the OS (epg cache for instance), another chunk is reserved for the fixed size file used for the time shift buffer.
Also the EXT3 file system reserves 5% of the space for use by the root user.