From my investigation the 'BIN' directory is also 'needed', since it installs files into 'Program Files\ATI Technologies\ATI Control Panel'. To name: atiicdxx.dll atiicdxx.ini atiicdxx.sys atiicdxx.vxd atricdxx.dft atricdxx.enu atiicdxx.dll defines the following symbols: DoDetection, QueryValue, QueryValueString, DoDetectionEx atiicdxx.vxd seems to do things with BIOS32 Service Directory and PCI stuff. atiicdxx.sys has functions for dealing with port (I/O port?) reading/writing and register reading/writing. The OEMInstall.bmp is safe to go, since it, even using setup with -s, gets replaced by a built-in logo from ATi. And saves another 1.3 MB. AtiCIM.dll and atiicdxx.dll are not even linked in to any other application I could detemine through DLLArchive. The vxd, sys files need closer investigation, but it is weird, nothing in the registry, but they are copied over to the destination folder and apparently don't seem to serve any purpose?