> Те самые 10-ки Гб в C:\W*

вы когда винду в последний раз видели ?

это 2012r2, установлен офис, все обновления и еще кое-что.

--- /cygdrive/c/Windows
    8.8GiB [##########] /Installer
    6.6GiB [#######   ] /WinSxS
    3.7GiB [####      ] /System32
  679.8MiB [          ] /SysWOW64
  581.1MiB [          ] /assembly
  502.3MiB [          ] /SoftwareDistribution
  446.5MiB [          ] /Fonts
  304.4MiB [          ] /Microsoft.NET
  158.2MiB [          ] /servicing
  149.7MiB [          ] /IME
   98.3MiB [          ] /InputMethod
   77.4MiB [          ] /Globalization
   67.0MiB [          ] /ServiceProfiles
   38.9MiB [          ] /Speech
   19.6MiB [          ] /Boot
   15.5MiB [          ] /media
   14.8MiB [          ] /Inf

это 2008r2, без офиса, но с обновлениями и еще кое-чем:

--- /cygdrive/c/Windows
    5.7GiB [##########] /winsxs
    1.6GiB [##        ] /System32
  619.9MiB [#         ] /SysWOW64
  606.7MiB [#         ] /assembly
  338.7MiB [          ] /Microsoft.NET
  276.3MiB [          ] /Fonts
  123.6MiB [          ] /IME
   61.6MiB [          ] /Help
   46.1MiB [          ] /servicing
   44.8MiB [          ] /SysMsiCache
   40.1MiB [          ] /inf
   23.1MiB [          ] /SmartFix
   16.1MiB [          ] /Installer
   14.3MiB [          ] /Boot
   11.1MiB [          ] /Globalization