The Mother Board

On my newly self built computer I have looked at the properties of my system disk. It's showing:
- used space 46.9 GB
- free space 884 GB
- Capacity 931 GB

However when I run a space analyser, called WinDirStat, it shows me that the folders and files on the disk total only 16.0 GB.

Why such a huge difference?

Just curiosity, really. I'm not short of space. It's not a big problem ... I hope.

There is a huge difference in "unformatted" space versus "formatted" space on a hard drive. Some space must be allocated to the file access tables, or FAT. And also the OS will create a small hidden partition for reference to the drive specifics, format type and space. This hidden partition may take up to 10% of the total capacity.
Some files and folders, especially those of the OS, may be hidden from those diagnostic or checker programs. Best is to use the resident program. Select "My Computer". Right click on the drive, choose 'properties'.
Also, in Administrative Tools/Computer Management/Disk Manager you will get a full disclosure of the entire drive and partitions.

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F@H.. to solve mankind's maladies.. in our lifetimes!

could be that 30 gigs is in use as both pagefile (pagefile.sys), and hibernation file (hiberfil.sys).
if you unhide system files on the root of your c: drive, you'll prolly see these two files show up as around the 30 gigs difference.

how much ram do you have installed in your machine?

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