macOS · Mac · Everyday fixes

Reset NVRAM when things misbehave

NVRAM stores display resolution, sound and boot preferences. A reset fixes a surprising number of weird glitches.

  • Difficulty Easy
  • Estimated time 3 min
  • Platform macOS
  • Last updated
Reset NVRAM when things misbehave — schematic diagram

Before you start

Low risk. This change is reversible — you can return to the previous state without professional help or data loss.

Steps

  1. Shut down the Mac completely (not sleep)
  2. Press power, immediately hold Option + Command + R for about 20 seconds
  3. Release when you hear the chime or see the second startup logo
  4. Boot normally — resolution and audio glitches are often gone

How to verify the fix

The Mac boots normally and the resolution/audio glitches that prompted the reset are gone.

If this didn't fix it

Glitches return after a normal boot — NVRAM wasn't the cause; check display settings and audio output next.

Next stop: the related fixes below, or start a guided diagnosis.

Related fixes

Still stuck? Diagnose my problem Browse all Mac fixes