SpaceSniffer is a great utility to find large files on your hard drive. It will analyze your hard drive and display your files as blocks. The larger the file, the larger the block. By double-clicking on a block you can quickly find large files that are hidden deeply on your hard drive.
Common Large Files: Hiberfil.sys & Pagefile.sys
Some very large files on your hard drive are usually hiberfil.sys and pagefile.sys.
The hiberfil.sys is a system file: If you are using the hibernation feature of Windows 7/Vista, Windows will create a copy of your RAM on your hard drive when it hibernates, so the file can be quite large.If you are not using the hibernation feature of Windows 7, you should get rid of the hiberfil.sys. If you don’t know how to delete the hiberfil.sys, read our tutorial: How to delete hiberfil.sys in Windows 7.
The pagefile.sys is as large as your virtual memory. When your real memory is full, Windows will start using the virtual RAM. The virtual memory size can be customized, but you should not set your virtual memory to 0MB.As a rule of thumb your pagefile.sys should be twice as large as the amount of RAM in your system, e.g. 4GB if you have 2GB RAM. As you can see this will be quite a large file on your drive, but should not be deleted.
Two Free Disk Analyzer Utilities
There are two other great free disk analyzer for Windows 7 that you should be aware of, because they can create a tree or pie chart of your hard drive and that is extremely helpful when it comes to finding large files in Windows 7.
