Repeated Beeping & Lag on First Boot When Plugged In – Predator Helios Neo 16 PHN16-71

Lee_03

Hi everyone,

I’m having an issue with my Acer Predator Helios Neo 16 (PHN16-71) that’s been happening for a few months, and I’m hoping to get some guidance.

Symptoms:

• When powering on for the first time of the day while plugged in, the laptop beeps repeatedly on the startup icon screen.
• No beeping if starting on battery only.
• When plugged in, I hear a short hissing sound that stops once the battery is full.
• To avoid the beeping, I wait to plug in the charger until the loading icon appears below the Acer startup logo.
• Performance mode (fan spins faster) only becomes available a few minutes after boot.
• Laptop feels very laggy immediately after first boot, even when plugged in.
• Battery is not empty — I keep the laptop charging while sleeping.

Timeline:

• The issue started a few weeks after I replaced the CPU cooling fan due to a failure.
• The problem has persisted for several months now.

Question:
Could this be related to the fan replacement (hardware connection issue), battery/charging system, or motherboard sensors?
Any tips on what I should check or reset before sending it in for service?

Thanks in advance for any insights!

Puraw

https://community.acer.com/en/discussion/727955/repeated-beeping-lag-on-first-boot-when-plugged-in-predator-helios-neo-16-phn16-71

Hello Lee_03,

I have the same Predator Helios Neo 16 (PHN16‑71) and haven’t experienced any “hissing” or repeated beeping during startup. Based on your symptoms:

• Fan noise: When the fans ramp up to full speed (e.g., in Performance Mode), they will sound loud — that’s normal.
• Beep alerts: Whenever AC power is restored or interrupted, the laptop will alert with a single beep — this is an Acer feature.
• Multiple beeps: If you hear several in a row, it almost always means the AC adapter plug isn’t fully seated.
  • This is a very common issue with this model — Acer has even published a support guide.
  • Push the DC plug all the way in until you hear and feel a loud, distinct click. A partial connection can cause intermittent power and repeated beeps.
• Other possible causes: If you’re already fully inserting the plug, check the AC cord or plug, especially if you use:
  • An extension cord
  • A multi‑socket power panel
  • Any kind of AC plug adapter for the wall outletThese can introduce loose connections or voltage drops that trigger the beeps.

If the beeping still continues after confirming a secure DC plug and reliable wall connection, try another compatible Acer adapter before considering service.