Drivers from the maker (Microsoft is really hit and miss on that.) Also turn off this.
If you have a HDD, go ahead and run the defrag after the usual CHKDSK /F/R/X
After that you have to really dive in to see if you can find the lag.
I happened to install the Creators Update on my Windows 10 laptop. Unfortunately, my laptop started to lag substantially after the update. Booting took much longer than usual and no app opened without any lag. Even the start menu took some time to execute!
In the light of all these complications, I decided to roll back to the previous build, the one which I had before i.e. 1607. However, as soon as windows rolled back, I realised that my laptop wasn't as snappy as before. It continued to lag but not as much as was the case after the Creators Update. I contacted people at Microsoft Support and one of their online correspondents, while taking command of my laptop over the internet, ram some tests, generated some reports, disabled a number of programs scheduled to execute on start-up and deleted temporary files.
This had the effect of putting an end to all the lagging. But, even now, my laptop isn't as snappy as it should be. Apps still execute after some delay and the gaming experience is not the same.
Does anybody know what should I do?