The files are installed to a hidden system folder usually located at: C:\Windows\System32 (for 64-bit compatibility files) and C:\Windows\SysWOW64 (for 32-bit game files on a 64-bit system). Note: You do not need to manually move files here; the installer does it automatically.
Even on a 64-bit OS, DirectX 9 runs in 32-bit compatibility mode. Installing the full runtime ensures both 32-bit and 64-bit applications find required .dll files without conflicts. directx 9 download windows 7 64 bit better