Yes it would, but it should work. Actually, I think I know of a way you could do it so as to keep WHQL signing intact. What if you renamed the file during the compression stage? You would have the 376/378 folder and the fasttx2k folder with their identically named files in them. fasttx2k.sys would be compressed and copied from the fasttx2k folder. From the 376/378 folder, fasttx2k.sys would be compressed and named fast378.sy_ or something. Change the associated txtsetup.sif entries and you're golden. And since fast378.sys would only be used during textmode setup, the WHQL issue is resolved. And to clarify for others, dosnet.inf patching is only needed for those initiating setup via winnt32.exe (in other words, from a WinPE or DOS startup disk). And unfortunately, the idea above wouldn't work for dosnet patching (since dosnet uses all the files).