You're looking for a piece of software related to CPU management. Here are a few options:
The software is often hosted on developer forums or reputable software archives (like MajorGeeks or Softpedia). It is typically a very small file (usually under 1MB). cpu core parking manager 3 download
Ideally, this transition should be instant. However, many users experience micro-stuttering or input lag in games because the operating system is too slow to wake up the parked cores, or it parks them too aggressively during gameplay. You're looking for a piece of software related