u/3toe

I have a pre-built desktop from Cost Plus Gaming:

Essentials Tier - M1 Flow - AMD Ryzen 5 9600X / Nvidia GeForce RTX 5060 8GB GDDR7 / 2T NVME PCIe 4.0 | 32GB DDR5-6000 MHz (ARGB)

It was working fine for almost a year until Microsoft pushed an update. I let the computer start the update and went to bed. The next morning I found that it turns on and everything lights up inside the case, all fans are running, but no peripherals function.

The USB ports don't provide power (so I can't use mouse, keyboard, etc... wired mouse with LEDs doesn't even light up when plugged into this system)
Neither the GPU nor the MoBo's display output will work (monitor detects no signal)
I can power the computer down by long pressing the case's power button.
The case button that changes the color of the fan's LED still works.
The motherboard status LED for BOOT comes on and stays on after 10 seconds, which, according to the manual, means it's not getting to the OS.

I tried the following:

Unplugging the power cable for 30 minutes and rebooted
Checked the RAM sticks were in the right slots, removed and cleaned each stick of RAM, tried running the system with each stick independently
Removed the GPU card and tried displaying from the internal gpu
Removed the SSD and tried booting
Verified all my peripherals work with my functional laptop

Is there anything else I should try? I'm not super knowledgeable with computers specifically and this sort of feels like a SW/FW thing, but I am an electrical hardware engineer with some relevant tools (multimeter, chiefly), so I can try some troubleshooting tips if you have any. And yes I am working with the customer support people who have been nice, but it's a long weekend so I'm not going to hear back from them until Tuesday. Thank you in advance.

Environmental test labs with snow generation

External devices no longer work with computer after recent Windows update.