[SOLVED] PC Won’t POST After Cleaning It Inside - White CPU EZ Debug LED Lit

[charlaten]

Background: My PC used to work like a charm for a couple years, but I spent some time cleaning it inside and seemed to have caused an issue preventing it from booting. I’ve outlined the exact circumstances below and what I’ve done to troubleshoot.

Issue: When I power on my PC, it does not complete the boot up/POST. All I’m able to see is the white ‘CPU’ LED lit on the mobo EZ Debug panel. I fear I may have static-shocked the mobo.

Question: Do you have any other recommendations on what I should check before I make a plunge and purchase a new mobo and CPU?

Troubleshooting Steps Taken:

1. Unplugged and replugged all cables, cards, drives, and RAM
2. Removed the CMOS battery for 5+ minutes
3. Removed as many drives, cards and cables as possible before booting. [1} I tried booting with just my M.2 SSD and graphics card plugged in (graphics card is necessary, this CPU doesn’t have onboard graphics) [2] I also tried with the secondary SDD and the graphics card.
4. Removed RAM (2x), tried reseating, rotating (4 slots), and using just one RAM stick

Workflow:

1. My computer’s fans were getting noisy, so I decided to clean it. I used a lot of canned air to move as much dust as possible.
2. Without thinking, I also used a rag to wipe it down inside. I think this could have been the issue, it is a regularly staticky type of rag.
3. When I plugged the computer back in and booted, it didn’t POST. I believe the white CPU led was on the EZ Debug panel, but I can’t remember exactly.
4. I noticed there was some liquid on the M2 SSD, likely from the canned air. Foolishly, while the PC was on, I just ran my finger across the SSD to remove the liquid. The PC then shut down.
5. Then the PC kept doing a pulse boot, where it would try to start for just about a half second, before turning off again.
6. I reseated all cables and tried again. At this point, the PC would turn on and stay on, but not POST. The screen stayed black and the white CPU light on the EZ Debug stayed lit.
7. I tried all other troubleshooting steps above, but nothing changed.

System:
Motherboard: MSI - Z390-A PRO ATX LGA1151
Processor: Intel - Core i5-9400F 2.9 GHz 6-Core Processor - LGA1151 - BX80684I59400F
Graphics Card: Gigabyte - GeForce GTX 1660 6 GB OC - GV-N1660OC-6GD
Primary Storage: Crucial - P1 1 TB M.2-2280 Solid State Drive - CT1000P1SSD8
Secondary Storage: Corsair Force Series GT CSSD-F240GBGT-BK 2.5" 240GB SATA III MLC Internal Solid State Drive
RAM: G.Skill - Aegis 16 GB (2 x 8 GB) DDR4-3000 Memory - F4-3000C16D-16GISB
Audio Card: Asus Xonar DGX - 09-YAA0Q1-0UAN0BZ
Power Supply: EVGA - SuperNOVA G2 650 W 80+ Gold Certified Fully-Modular ATX Power Supply - 220-G2-0650-Y1
CPU Cooler: Corsair H60 CPU Cooler
Case: Corsair - 200R ATX Mid Tower Case

Additional Notes:
- I don't have a spare mobo, graphics card, or PSU for testing

 

[kerberos_20]

try reseating cpu

 

[charlaten]

try reseating cpu

Okay, will do. I was assuming that this wouldn't be needed since the computer ran fine for ~3 years without an issue and I've never unseated the CPU. But maybe it got a little jostled while cleaning.

 

[charlaten]

I tried reseating the CPU, but it didn't do the trick. It seems that I may have static-shocked the mobo and/or CPU. I ended up replacing both the mobo/CPU and all is working again.