I have an odd problem. I jumped from driver 16.4.1 to 16.6.1 and saw an increase in boot time to Win7 desktop on my SSD.
If you want to sit through a boring 4 minute video I recorded on my phone:
In the video I show a restart on 16.4.1. Then I uninstall with DDU and install 16.6.1, making sure not to install Gaming Evolved/Raptr. Then I show 4 restarts on 16.6.1. Nothing else. Hopefully you should see that my boot time increases, the "please wait" and "welcome" messages of Windows 7 don't normally appear but after 16.6.1 it hangs there for several seconds. Six seconds is not a big deal but I'm petty about stuff like this.
I looked at the difference of Windows event viewers between 16.4.1 and 16.6.1 and saw at boot-time 16.6.1 has an error from source ATIeRecord. This thread suggested stopping AMD External Events Utility loading on startup and having done that my boot times are back to normal. The only problem is by doing this I'm noticing increased loading times with other applications, for instance Steam. If I toggle AMD External Events utility on and off and I can see a noticeable difference in the loading time of Steam.
Might anyone know what the issue is?