Rgb light flicker when usb plugged in

[christian244]

Hi guys, long time fan of the LTT channel, but first post on the forums. I’ve got a strange issue at hand, one that I can’t say I’ve encountered before. I have my beginner certifications through comptia and I’ve been hands on with computers for most my life, so the only thing i can come up with is that is could be a fault in the motherboard allowing power to go through the USB’s? Not sure.

I have a usb hub that is powered separately from my pc via an outlet, but is connected to my pc via USB. Whenever I plug it into certain ports, it triggers some usb lights to activate or erratically flicker on my computer. Any ideas? The 2 out of the 4 ports on my pcie usb expansion card allow this behavior. The other two don’t seem to have an issue. Plugging it in on the top IO of the case only seems to light up the MSI logo for my aio. 

 

video: (has to be a google drive link since it’s past 20 mb ) https://drive.google.com/file/d/1TfHOdcEG7UOw9LTpQfAK5zjNmdUfwyEX/view?usp=drivesdk

[-rascal-]

What are your system specifications? CPU? Motherboard? PSU?

What is the make and model of the PCI-E to USB 3.0 expansion card?

 

USB natively supplies 5V power, in addition to data, so that's normal.

 

If what you have is ARGB fans, etc, it is power through the 5V power on the motherboard. USB is also 5V.

Possibly either:

• PCI-E to USB expansion card has some sort of fault
• Motherboard is shorting to the chassis/case (e.g. check your stand-offs)
• USB Cable shown in your video is jank

 

[christian244]

5 hours ago, -rascal- said:

What are your system specifications? CPU? Motherboard? PSU?

What is the make and model of the PCI-E to USB 3.0 expansion card?

 

USB natively supplies 5V power, in addition to data, so that's normal.

 

If what you have is ARGB fans, etc, it is power through the 5V power on the motherboard. USB is also 5V.

Possibly either:

• PCI-E to USB expansion card has some sort of fault
• Motherboard is shorting to the chassis/case (e.g. check your stand-offs)
• USB Cable shown in your video is jank

 

i9 12900k, pro z790-p wifi ddr4, evga bp series 750w (or a 700? i forget)

the pcie usb 3 expansion card can be found here on amazon: https://www.amazon.com/dp/B072LS4JH7?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1

I previously had an Inateck KTU3FR-4P usb expansion card, and it worked perfectly, didn't cause any issues and didn't cause strange rgb flashes. But about 2 days ago, it decided to give me the middle finger and quit working. The USB connection would seat, but it would disconnect and reconnect every couple of seconds. One of the blue guide plastics (found in most USB 3.0 ports) popped out a while back and I'm guessing that the pins in the port just now decided to short out or something. Not sure. 

 

Anyways, I decided to bite the bullet, find a card with great reviews, and dropped about $23 on the new card. Works great, gives me those RGB issues.

My case shouldn't have any standoff shorts since I haven't done any "invasive surgery" in a while to the PC. The cable could be bad, but it's never given me issues before.

[-rascal-]

18 hours ago, christian244 said:

i9 12900k, pro z790-p wifi ddr4, evga bp series 750w (or a 700? i forget)

the pcie usb 3 expansion card can be found here on amazon: https://www.amazon.com/dp/B072LS4JH7?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1

I previously had an Inateck KTU3FR-4P usb expansion card, and it worked perfectly, didn't cause any issues and didn't cause strange rgb flashes. But about 2 days ago, it decided to give me the middle finger and quit working. The USB connection would seat, but it would disconnect and reconnect every couple of seconds. One of the blue guide plastics (found in most USB 3.0 ports) popped out a while back and I'm guessing that the pins in the port just now decided to short out or something. Not sure. 

 

Anyways, I decided to bite the bullet, find a card with great reviews, and dropped about $23 on the new card. Works great, gives me those RGB issues.

My case shouldn't have any standoff shorts since I haven't done any "invasive surgery" in a while to the PC. The cable could be bad, but it's never given me issues before.

 

Given the symptoms you are mentioned (connecting/disconnecting) and the other USB port being damaged, sounds like the USB expansion card.

It depends on how the 4x USB parts are schematically wired and layout of the PCB; when one acts up, it can mess with the neighboring ports.

 

My suspect is the expansion card; however, it doesn't quite explain why the RGB goes nuts with the font I/O USB port, though.

 

What happens if you temporarily remove the PCI-E USB expansion card?

Does the front I/O USB port still cause the RGB to behave funky once you remove the expansion card?

 

[christian244]

On 6/22/2025 at 12:17 AM, -rascal- said:

 

Given the symptoms you are mentioned (connecting/disconnecting) and the other USB port being damaged, sounds like the USB expansion card.

It depends on how the 4x USB parts are schematically wired and layout of the PCB; when one acts up, it can mess with the neighboring ports.

 

My suspect is the expansion card; however, it doesn't quite explain why the RGB goes nuts with the font I/O USB port, though.

 

What happens if you temporarily remove the PCI-E USB expansion card?

Does the front I/O USB port still cause the RGB to behave funky once you remove the expansion card?

 

The front I/O port only causes the AIO RGB logo to illuminate, not the whacky disco party, which can be observed in the video. 

 

I would lean towards your suspicion about it being the expansion card, since it never behaved this way before the new card. You'll have to give me some time before I can test that for sure, as I'm out for a few days.