The bios change is only for boot sequence and what it looks to boot to in what order. No other changes are made to the bios. In reality I suggest everyone have their boot sequence set to the cdrom first just in case there is a bootup issue then you can still use a boot disk to get to the data.
I fully understand wanting to wait and we can work in another direction for now.
We can take a look at what programs may be loading you don't know about by doing the following.
Download Autoruns from the link in my signature below:
1: Extract the Autoruns Zip file contents to a folder.
2: Double-click the "Autoruns.exe".
3: Click on the "Everything" tab
4: Remove any entries that mention "File Not Found" by right-clicking the entry and select Delete.
5: Go to File then to Export As or Save in some versions.
6: Save AutoRuns.txt file to known location like your Desktop.
7: Attach to your next reply.