OK, I think then ARCHICAD is using the Temporary folder of the operating system for these files. Recently I have change the related environmental variables on my sytem to "D:\Temp" and for me the Point Cloud Temp files are saved there.
So I would recommend that you change the path the TEMP and TMP environmental variables of Windows to point to another drive. That will free up even more space on your SSD because other applications are using these locations as well to dump their temp file (which are then later may not be cleaned up).
This is for Windows 7 but I am sure it is pretty similar in Windows 8.1:
http://answers.microsoft.com/en-us/windows/forum/windows_7-files/change-location-of-temp-files-folde...
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