Rattling noise in my OMEN 40L Desktop GT21-0005nc

[Shomzo]

Hi,
I'm having issues with a rattling sound that only occurs when the PC is not put under any stress. When idling, browsing the internet or playing games that are not demanding such as League of Legends etc., a rattling sound occurs. To my knowledge, the sound is coming from the back part of the case, possibly hinting at a PSU fan issue.
These are the full specs:

MODEL

OMEN by HP 40L Gaming Desktop GT21-0xxx

OPERATING SYSTEM

Microsoft Windows 11 Home

- Release ID: 2009

- Version: 10.0.26100

- Build: 26100

CPU

AMD Ryzen 5 5600X 6-Core Processor             

- Clock speed: 3701MHz

- Description: AMD64 Family 25 Model 33 Stepping 0

GPU

NVIDIA GeForce RTX 3070

- Refresh rate: 144Hz

- Driver version: 32.0.15.7688

RAM

HP37D4U1S8HC-16XR   

- Capacity: 16GB

- Type: DDR4

- Default clock speed: 3733MHz

HP37D4U1S8HC-16XR   

- Capacity: 16GB

- Type: DDR4

- Default clock speed: 3733MHz

AUDIO

Yeti Classic (OAB7)

NVIDIA High Definition Audio

Realtek High Definition Audio

NVIDIA Virtual Audio Device (Wave Extensible) (WDM)


Some videos to provide further information:
https://youtube.com/shorts/1YdOL96JfxY?feature=share
https://youtube.com/shorts/8mdOb90vn4o?feature=share 

I originally thought the sound was caused by a faulty GPU fan. After that I thought it was maybe caused by the exhaust fan. However, lately, when listening closely to the back part of the case, it seems to me that the PSU fan might be the cause. I'm guessing its either dust particles stuck to the fan or a faulty fan bearing. I would also like to know if anyone has an idea with regards to what PSU is used in these pre-builts. My warranty has unfortunately expired last year, so I might look for a replacement PSU (or the other faulty part) myself.

Thank you for your time and help.
Regards, Shomzo.

[Max3Aj · Accepted solution]

@Shomzo, Welcome to HP Support Community. 

Thank you for posting your query, I will be glad to help you. 

From your detailed description and the videos you’ve shared, it does sound like the rattling noise is likely coming from the PSU (Power Supply Unit) fan, especially since it occurs during low-load or idle scenarios when the PSU fan may be spinning at lower RPMs or intermittently turning on/off.

Possible Causes:

1. Dust or debris caught in the PSU fan.
2. Worn-out or misaligned fan bearings.
3. Loose internal components or cables brushing against the fan blades.
4. Vibration from the PSU housing not being tightly secured.

Recommended Steps to Troubleshoot:

1. Visual Inspection (Safety First!)

• Power off and unplug your PC.
• Open the side panel and inspect the rear PSU fan area.
• Use a flashlight to check for:
  • Dust buildup
  • Loose cables
  • Any visible damage or misalignment

2. Clean the PSU Fan

• Use compressed air to blow out dust from the PSU vents (from the outside if the PSU is sealed).
• Avoid opening the PSU casing itself unless you're experienced, as it contains high-voltage components.

3. Check for Loose Screws or Mounts

• Ensure the PSU is firmly secured to the chassis.
• Check if any screws or brackets are loose or vibrating.

4. Test with Side Panel Off

• Carefully run the PC with the side panel off and listen closely to isolate the noise.
• You can gently press on the PSU or surrounding areas to see if the noise changes or stops.

PSU Replacement Info

If the noise persists and you suspect a failing PSU fan, you may consider replacing the PSU.

• The OMEN 40L GT21-0005nc uses a standard ATX PSU, so most aftermarket ATX PSUs will be compatible.
• HP typically includes Cooler Master 750W or 800W Bronze/Gold-rated PSUs in these models, but the exact model may vary. 

We suggest you please visit the nearest HP authorized service center, the service team will check and assist you further. 
Kindly follow this link to locate the nearest HP service center: HP® Service Center Locator - Nederland | HP® ondersteuning
(Select the country from the dropdown menu and enter the city name or pincode) 
 

I hope this helps. 

Take care and have a good day. 

Please click “Accepted Solution” if you feel my post solved your issue, it will help others find the solution. Select "Yes" on the bottom left to say “Thanks” for helping! 

Max3Aj

HP Support