you clearly did not read my post properly.. as I wrote that I am already using it!

but on TOP of that , compressing the DDS (with GIMP in my testcase ) got me an extra 50% gain.
60MB dds file with CM compress tool was taking approx 4MB of SSD space,
I compessed it with GIMP to BC3 / DXT5 , resulting in a 20MB file.
The CM compress tool then made this file take only 2MB of space on my SSD.
So I gained an extra 50% of diskspace for this file, even though I was already using CM Compress tool , and the file was already compressed.
Hence I want to find a tool that I can run to do a mass / batch compress of all the DDS files in my content folder,
which will save me I estimate at least 100GB of disk space..
Since my 1TB SSD is almost full , with only Assetto corsa on it , I would preffer gaining some space by having the DDS files compressed as best as possible...