Question New PC No Longer Booting (MOBO light turns off when power button pressed)

[ccc_mmm]

Hi,

I have an issue that is driving me crazy. I have a new build, all new parts, that was working fine until I installed another fan on the CPU cooler (removing the changes I made does not fix the issue). My PC was working perfectly and I decided to install a second fan to the Noctua cpu cooler. I attached the new fan, plugged it in, and after that the PC won't boot: no fans, etc. The only thing that turns on is the motherboard power light (and light on CMOS button), which happens when I plug-in the power cord. When I press the power button, either on the case or on the motherboard directly, it turns off. It doesn't turn back on until I unplug and re-plug the power cord.

I didn't touch the PSU in the process of installing a fan, but I have ensured everything is plugged in correctly since. I also have a PSU tester arriving today just to be sure something didn't happen with the PSU.

Does anyone have any idea what could be going on? I'm relatively inexperienced with troubleshooting hardware and would appreciate any suggestions! Thank you!


Here are the specs:

CPU: AMD Threadripper 3960X 3.8 GHz 24-Core Processor
CPU Cooler: Noctua NH-U14S TR4-SP3 82.52 CFM CPU Cooler
Motherboard: Gigabyte TRX40 AORUS MASTER EATX sTRX4 Motherboard
Memory: G.Skill Trident Z RGB 128 GB (4 x 32 GB) DDR4-3600 CL18 Memory
Storage: Samsung 970 Evo 1 TB M.2-2280 NVME Solid State Drive
Storage: Samsung 970 EVO Plus 2 TB M.2-2280 NVME Solid State Drive
Video Card: NVIDIA GeForce RTX 3090 24 GB Founders Edition Video Card
Case: Fractal Design Define 7 XL ATX Full Tower Case
Power Supply: be quiet! Dark Power Pro 12 1200 W 80+ Titanium Certified Fully Modular ATX Power Supply
Case Fan: Noctua A14 PWM chromax.black.swap 82.52 CFM 140 mm Fan (x5)

 

[David329302]

Make sure you pugged into the right pins for the case when you installed the motherboard. And you have one hell of a pc build.

 

[ccc_mmm]

Make sure you pugged into the right pins for the case when you installed the motherboard. And you have one hell of a pc build.

The pins should be correct, as it was running previously and I didn't change any of those connections. I will double check it to be safe though. Thanks for the suggestion.

And thanks

 

[David329302]

What are you using your pc for if you don't mind me asking? And I would take out and reinstall the RAM sticks in a different patterns until you get to windows.

 

[ccc_mmm]

What are you using your pc for if you don't mind me asking? And I would take out and reinstall the RAM sticks in a different patterns until you get to windows.

It's mainly for simulation/machine learning research.

No luck with the RAM, I tried using only two of the sticks as well as rearranging them.