Question Hunting the short circuit. Need help!

[silverhammer92]

Hi Guys

Today I built my new pc and it kinda runs I did install Windows 10 (because I already had it on a drive) and after getting the drivers for Ethernet, I started updating Windows.

Up to here everything worked perfectly fine. But during the installation of the Windows Updates the PC started using more power and a strange noise started arising. My first thought was, that a wire was touching a fan. This short video shows the flickering noise. At sec. 26 you can hear the fans spinning up, at sec. 29 you hear the flicker.
https://photos.app.goo.gl/a9Du6dW8TYATApU5A

I reproduced the problem multiple times attempting to locate the source of it, when suddenly two loud "peng" did trigger my power fuse to disconnect. You can hear the peng (and my gasp) in this short video:
https://photos.app.goo.gl/Zc7DWrN8TcMKuEzg7

So this is what I am getting from this:

• since the power in the appartment went out, it must be a short circuit.
• the Computer would still run even during the short circuit (also during the first peng which did not yet disconnect the power)
• the short circuit only seems to happen, when the pc uses more power. (This might be wrong and only the effects get strong enough to be noticed...)

The computer still works fine. But I need help. How can I localize the short circuit?

Many thanks for your assistance!


p.s. I do have a multimeter which might help, but I reall don't know where I should probe...

 

[SkyNetRising]

Start by listing full specs of your system. Include model name of PSU.

I'd suspect your PSU to be blowing out power fuses.
Noise is probably being made by that plastic thing, you have at top of motherboard between top fan and EPS cables.

 

[silverhammer92]

Start by listing full specs of your system. Include model name of PSU.

I'd suspect your PSU to be blowing out power fuses.
Noise is probably being made by that plastic thing, you have at top of motherboard between top fan and EPS cables.

Thanks for looking into this.

This is a piece of cardboard which I placed between the fan and the cpu-cable because I thought, that the cables there would be touching the fan. It is not conductive and obviously as I know now was not the problem so I removed it again.
It was basically just a test to see if my assumption was correct...

so no, the cardboard is not making the noise you hear.
How can I verify your theory about the PSU blowing out powerfuses?

 

[silverhammer92]

For the specs, this is my pc:

1. MSI MPG B650 EDGE WIFI ATX AM5 Motherboard
2. AMD Ryzen 7 7800X3D 4.2 GHz 8-Core Processor
3. Deepcool LS720 SE WH 85.85CFM Liquid CPU Cooler
4. G.Skill Ripjaws S5 32 GB (2x16 GB) DDR5-6000 CL30 Memory
5. Samsung 980 Pro 2 TB M2-2280 SSD
6. be quiet! Pure Power 12 M (1200 W) Power Supply
7. NZXT H9 Flow ATX Mid Tower Case
8. Asus Rog-Strix-RTX4090-024G-White (currently not installed)

 

[Misgar]

Where abouts is your "blowing power fuse"?

Is it a small metric 20 x 5mm fuse like the one below? These used to be fitted in early AT PSUs, but you're unlikely to find one in a modern ATX PSU.

If you're in the UK, is it a 13A fuse in the mains plug of the IEC cable plugged into the back of the computer?

Perhaps it's a piece of 30A fuse wire on a ceramic holder in a mains distribution panel (like the one in my home).

 

[silverhammer92]

Where abouts is your "blowing power fuse"?

Is it a small metric 20 x 5mm fuse like the one below? These used to be fitted in early AT PSUs, but you're unlikely to find one in a modern ATX PSU.

If you're in the UK, is it a 13A fuse in the mains plug of the IEC cable plugged into the back of the computer?

Perhaps it's a piece of 30A fuse wire on a ceramic holder in a mains distribution panel (like the one in my home).

I see but it is a modern PSU and since the pc starts normally every time, I don't think a blown out power fuse is the problem...
Also opening the PSU would void the warranty so I don't want to do it if I don't need to....

 

[SkyNetRising]

For the specs, this is my pc:

1. MSI MPG B650 EDGE WIFI ATX AM5 Motherboard
2. AMD Ryzen 7 7800X3D 4.2 GHz 8-Core Processor
3. Deepcool LS720 SE WH 85.85CFM Liquid CPU Cooler
4. G.Skill Ripjaws S5 32 GB (2x16 GB) DDR5-6000 CL30 Memory
5. Samsung 980 Pro 2 TB M2-2280 SSD
6. be quiet! Pure Power 12 M (1200 W) Power Supply
7. NZXT H9 Flow ATX Mid Tower Case
8. Asus Rog-Strix-RTX4090-024G-White (currently not installed)

Is your pc blowing out power fuses even with 4090 removed from system?

 

[silverhammer92]

I visited a specialist and it turns out, that the ball-bearing of one fan of the AOI Water cooling is broken and causes the noises and short circuit. Disconecting that one fan solves the problem... So its a defect on arrival and the case is closed!