Settings that break things
- GPU driver registry packs (power-state, clock-gating, “DPM” values): black screens when a game starts, crashes, cards stuck at full power.
- Disabling CPU idle states / forcing 100 % CPU: more heat and fan noise, often no measurable gain.
- Turning off security mitigations or Memory integrity / VBS: security holes, and some anti-cheats (Vanguard) refuse to start.
- Disabling Windows Update or Defender for good: no security fixes, and some games stop updating.
- Interrupt / MSI priority hacks and boot options you can't easily undo.
Checklist for any optimizer
- Does it create a restore point first?
- Can every change be undone one by one — and all at once?
- Does it say what each change does and how risky it is?
- Does it keep away from drivers, BIOS writes and anti-cheat requirements?
- Does it promise a fixed FPS number? Walk away: gains depend on your hardware.
If something already went wrong
- Use a restore point from before the tweaks (Restore page in HKTweaks, or “rstrui” in Win + R).
- Black screens after a “GPU pack”: a clean driver reinstall (DDU in safe mode) removes the bad values.
- Vanguard errors after a tweak: see the VAN: RESTRICTION guide.
How HKTweaks helps
HKTweaks removed 34 settings for good because they could cause a blue screen or stress a CPU / GPU (driver keys, idle states, mitigations, interrupt hacks). The ones left show a risk level — safe, moderate, advanced, expert — and “Apply” only takes the safe ones unless you choose more. A restore point comes first, and Undo all puts every tweak back exactly as it was.
Still stuck? A real staff member answers in a ticket on our Discord.