Processor problem.

So hello, my processor is constantly loaded, at rest (games are not running, only the necessary programs) is loaded by 15-20% and sometimes jumps to 40-50%. Games began to sag in fps for 1-2 seconds. Even BioShock 2 sags sometimes. When BioShock 2 is running, the processor is 90-99% loaded. I have been struggling with this problem for a long time, I checked for viruses with a paid avast, doctor web kureit. When the computer restarts, strange programs are launched that devour my percent by 60-80% when the state is at rest, I immediately turn them off in the task manager. Computer configuration i7 3770, GTX 770, 2GB 8GB RAM.