Whining noises occur at reduced power levels - Deepcool PX850G
Whining noises occur at reduced power levels - Deepcool PX850G
Hello everyone. I recently purchased a new PC with the following specifications:
Power Supply Unit:
Deepcool PX850G 850W
Motherboard:
Asus TUF GAMING B650M-PLUS (WIFI)
Processor:
AMD Ryzen 5 7600
AIO CPU Cooling:
EKWB EK-Nucleus AIO CR240 Dark
GPU:
GTX 1050ti
When my PC is idle, the PSU or Motherboard VRM usually produces high-pitched noises. I have three videos to share:
1. https://youtu.be/DnslTQSWsbo – shows the noise during and when it stops
2. https://youtu.be/ngeRs-uNNTk – displays power usage drops on the wattmeter (Idle ~78W, mouse movement 94W)
3. https://youtu.be/qTdtJ7RfTFI?si=q6dvcKR4SiUznoS7 – footage with a disconnected GPU; the sound disappears when stressing the CPU
All readings were taken using the connected BenQ monitor, which used about 20W, so idle consumption is around 60W and drops to roughly 80W under heavy load.
The issue appears to be that my motherboard's VRM and possibly the PSU start making noises when power draw decreases from 80W to 60W. I found some options in the UEFI section "DIGI+VRM" that might help, but I’m unsure which would be suitable (and I don’t want to return parts).
This noise becomes noticeable only when interacting with text or commands, not during silent operation.
perform stress test on the PSU with OCCT, include water cooling on the tube to verify sound transmission, and use hwinfo to monitor temperature, voltage, and fan speeds. A log can be created from the data.
Under heavy pressure no complaints at all.
When I apply force to the tube while it whines – nothing occurs and the whining remains unchanged.
The fan operates at its minimum speed and temperatures are at their lowest, verified via s-tui.
OK, so that's the PSU 100%, I disassembled the Pc and separated PSU and motherboard, and it's definitely a fail of the PSU.
Video link: https://youtu.be/MZxrpfxnYrk?si=EzXTGw50cOy2su5w
I sent an RMA because fixing this in the expected way wasn't possible.
Two alternatives were considered: writing driver/daemon code to load a core for at least 80W, or building a mechanical device to constantly draw current from the PSU, like a resistor into molex.
These ideas seem impractical, so I'm hoping to find another PSU that won't complain while I work—such as text editing without any load on the CPU or GPU.