This message was posted on behalf of Intel Corporation
In regard to your question, actually it depends on the load of work on the computer, the cpu usage on a processor always fluctuates, it is not a steady value, it will depend on the programs that are currently running, the processes on the background and all the possible tasks that are in progress.
It is expected for the cpu usage to go up and down for the reasons provided above, specially if you are playing a game.
Which version of windows are you using?
In regard to the problem with the FPS dropping, I just wanted to let you know that the processor works with Intel® HD Graphics 4600, on the following link you will find the latest version of the graphics drivers for the graphics controller, in there you will be able to choose the operating system to install them:
Please let me know the results of trying the drivers above.
What is the model of the laptop?
Did you try a BIOS update on it?
Any further questions, please let me know.