What Is PRAM/NVRAM?

NVRAM (Non-Volatile RAM) — formerly called PRAM — stores small amounts of system settings that need to persist even when the Mac is off: display resolution, startup disk selection, speaker volume, time zone, and kernel panic information. Resetting it clears these stored settings and can resolve: startup issues, incorrect display resolution, missing sound after waking, wrong time zone, and issues starting from the wrong disk.

Reset NVRAM on Intel Mac

  1. 1

    Shut down the Mac completely

    Apple menu → Shut Down. Wait for the Mac to fully power off.

  2. 2

    Press power, then immediately hold Cmd+Option+P+R

    Press the power button. Immediately press and hold Command (⌈) + Option + P + R simultaneously. You need to press this combination before the grey startup screen appears — within 1–2 seconds of pressing power.

  3. 3

    Hold for two startup chimes (or 20 seconds)

    On Macs with a startup chime: hold until you hear the startup chime a second time, then release. On Macs without a chime (most post-2016 models): hold for approximately 20 seconds. The Mac may restart once during this process — keep holding.

  4. 4

    Check and reconfigure settings

    After reset: check System Settings for display resolution, Sound → confirm volume, System Settings → General → Startup Disk (set to your correct boot drive if it changed). The reset clears stored values back to defaults.

Apple Silicon Macs (M1, M2, M3)

Apple Silicon Macs store NVRAM differently and automatically validate and restore it during the startup process. There is no NVRAM reset key combination — restarting the Mac handles this automatically. If you are experiencing issues on an M-series Mac, a full shutdown and restart (not just restart) is the equivalent step.

Frequently Asked Questions

No — NVRAM contains only small system preferences, not your files, applications, documents or photos. Resetting it only affects settings like display resolution, startup disk selection, sound volume and similar low-level preferences. Your data is completely unaffected.
PRAM/NVRAM reset: clears stored system settings (display, volume, startup disk). SMC (System Management Controller) reset: resets the chip that manages power, thermal management, fans, sleep behaviour and LED indicators. SMC reset is the fix when a Mac has unusual behaviour like fan running at full speed, not sleeping, power adapter not recognised, or battery not charging. They address different issues — if one does not fix your problem, try the other.