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I have a 64GB SSD (formated to 59GB) as my main drive (C:). Windows and Rainmeter both tell my it's full (55GB atm to be precise, but I already deleted stuff). The thing now is that when I open the drive in the Explorer, and look up the individual files (including hidden ones) they don't add up to that amount:

  • Users 6,4GB
  • Nvidia 0,5GB
  • PerfLog 0,0GB
  • ProgramsData 0,9GB
  • Programs 2,4GB
  • Programs(x86) 3,0GB
  • SkyDriveTemp 0,0GB
  • Windows 20GB

As long as math suddenly has not changed in the last few month, this should not add up to more than 33,2. I'd expect a bit of a margin, but not that it would be 12GB!

Where are those 12GB and how can I free them?

I run Windows 8, 64bit, AMD Phenom II X4 955, 8GB RAM, and I also have a secondary 1.5TB HDD before you ask.

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Have you turned off hibernate? That's 8GB you'd free up. – Ash Jan 23 '13 at 9:39
You might want to try something like windirstat to visually see what's using that space. I find it helps a lot – Journeyman Geek Jan 23 '13 at 9:45
Also, the file size doesn't always match the size the file takes up on the disk, since small files still take up the block size. Not sure if you've taken that into account. – Ash Jan 23 '13 at 9:49
up vote 2 down vote accepted

Have you checked your pagefile and hibernation files? You need to disable the folder options for hidden and system files and you can find them here:


Depending on your configuration, this files can get quite big. In my case both sum almost 7Gb.

You can configure their behaviour/size in Advanced system settings > Performance > Advanced > Virtual memory and change the pagefile options. To disable hibernation, you can run the following command from an elevated CMD:

powercfg -h off

This step will disable hibernation, delete the hiberfil.sys file, and remove the Allow hybrid sleep and Hibernate after Power Options under Sleep. This will also disable fast startup in Windows 8.

For more information on how to optimize a HDD or SSD under Windows 8, I suggest you take a look at Sean's Guide.

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Ah, so I missed those system files. As I like the fast start up, and the page only is 8GB (=RAM) it'll have to be a bigger SSD if I want more for programs/games. Thank you. – Gregor A. Lamche Jan 23 '13 at 10:05
I suggest you get a HDD and put your hiberfile and pagefile on those. You will extend the life of your drive and free up a lot of space – VBwhatnow Jan 23 '13 at 10:46
@GregorA.Lamche You don't need to completelly turn off hibernation, you can just shrink it with the following: powercfg -h -size 50 (you can change 50 to a higher value if you want) – Peter Jan 23 '13 at 11:17

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