How can I connect the internal laptop fan of HP 255 G7 to an external power adapter?

[IamArash]

Hello,

I have an HP 255 G7 Notebook PC with the following specifications:

• CPU: AMD Ryzen 5 3500U

• GPU: Integrated Radeon Vega 8 (2GB)

• RAM: 12GB (8GB built-in + 4GB additional)

• OS: Currently running Windows 10 (have tested Windows 11 too)

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❗Fan Issue:

About 2 months ago, I started facing abnormal behavior with the laptop fan.
As soon as Windows boots up, the fan spins at maximum speed, even when the system is completely idle (confirmed via Task Manager with no active processes). After a few minutes—despite CPU/GPU temperatures being below 40°C—the fan suddenly stops completely and never spins again, no matter how high the temperatures go.

There are only two temporary workarounds:

1. Putting the laptop into Sleep Mode, then immediately resuming. This restarts the fan, but in 97% of cases, the cycle repeats: full-speed fan → sudden stop after a few minutes.

2. Restarting the system, which again re-enables the fan briefly, before the same issue happens.

🕓 The fan does not stop after a fixed duration—sometimes it runs for 2 minutes, sometimes even an hour before shutting off.

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🔧 What I’ve tried so far:

1. Reinstalled OS multiple times:

   • Windows 10 → Windows 11 → back to Windows 10

2. Changed Power Plans:

   • Switched between Balanced and High Performance

   • Set Max Processor State to 99%, and also adjusted Min Processor State

   • No long-term effect

3. Updated BIOS:

   • Reset to defaults, tried toggling "Fan Always On" (if available)

   • No impact

4. Safe Mode:

   • The problem still occurs even in Safe Mode

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🕹️ Other Observations:

• On very rare occasions, the fan behaves correctly.

• When I run games like CS2 or Dota 2, the fan may stop spinning after the game starts.
  But if I Sleep → Resume while the game is open, the fan works properly and continues working during gameplay.

• This trick does not work for lighter games like AOE, CS 1.6, or CS: Source.

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🔧 What I want to do:

I’m looking for a hardware workaround by powering the fan using an external adapter.

My idea:

• Disconnect the fan connector from the motherboard.

• Use a suitable DC adapter with correct voltage/amperage.

• Possibly use a matching fan socket or wiring adapter to connect the fan directly.

• Route the adapter wire through the DVD writer slot, which I can remove if needed.

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❓My Questions:

• What is the voltage and current requirement for the internal fan?

• What is the pinout or wiring diagram for the fan connector on this model?

• Is there a safe and recommended way to power the fan externally?

I would really appreciate any technical guidance or suggestions.
Thanks in advance!