Hey everyone, looking for some validation on a hardware failure that just happened today.
My system was working perfectly fine this morning while playing War Thunder. Before leaving, a standard Windows update popped up, so I hit "Update and Shut Down" and left.
When I came back at 6:00 PM tonight, the PC was completely unresponsive.
The front case power button did absolutely nothing. Strangely, my keyboard and USB accessories (Elgato, Arzopa portable monitor) were lighting up via standby power, but the actual PC internals (CPU fan, case fans, motherboard lights) were completely dead.
I spent tonight troubleshooting and ruled out a soft-brick/sleep loop:
Done a full CMOS clear/battery reset.
Attempted a deep capacitor power drain (holding the power button while unplugged).
Removed my **RX 7900 XT** GPU to get clear access to the **Asus PRIME B650M-A AX II**motherboard front panel headers.
Attempted to jump-start the PC by manually bridging the PWR_SW pins on the F_PANEL header with a flathead screwdriver (with wall power verified active).
**Result:** Absolute silence, no fan spin.
**The Smoking Gun:**
I finally pulled the main **24-pin motherboard power cable** and performed a paperclip jump test on pins 4 and 5 (PS_ON and Ground) with the wall outlet plugged in and the PSU switch turned ON.
**The fan inside the power supply box stayed completely still and did not spin at all.**
It looks like the sudden drop in voltage when Windows forced the shutdown at noon completely killed the main 12V rail on my PSU, though it managed to keep a tiny bit of 5V standby power flowing to the USBs before dying completely.
Thankfully, it looks like the PSU sacrificed itself and saved my GPU and motherboard.
Anyone else experiencing this?
PC Specs:
GPU: AMD Radeon RX 7900 XT
CPU: AMD Ryzen 7 7800X3D Raphael AM5 4.2GHz 8-Core
RAM: TeamGroup T-FORCE DELTA RGB 32GB (2 x 16GB) DDR5-6000 PC5-48000 CL30
SSD: WD Black SN770 2TB SSD
Motherboard: Asus PRIME B650M-A AX II
Power Supply: Corsair RM850 850 Watt 80 Plus Gold ATX Fully Modular Power Supply - White
Cooling / Fans: DeepCool AK620 High-Performance
CPU Cooler - White w/ Lian Li UNI Fan SL Infinity Fluid Dynamic Bearing 120mm Case Fan - 3
Exhaust: Lian Li UNI Fan SL Infinity Fluid Dynamic Bearing 120mm Case Fan - White - 2