It seems to me that in 1.1, disabling the A600 IDE controller does nothing. When I disabled it, I expected to be asked to reset the Minimig, but I was not, and even if I reset manually, hard drive files are still used even though the menu says A600 IDE is off.
The firmware tries to detect if anything regarding IDE is changed in the OSD menu, so it knows when to apply new settings. I noticed this myself - sometimes the IDE settings change doesn't get detected. If the OSD doesn't request to reset minimig, the setting change didn't get detected. What I usually do is change the type of the slave to something different and then try disabling it again.
So, without a request to reset minimig, the changed IDE settings will *NOT* get applied. I'll try to fix this in the near future.