Question PC randomly turns off, won't boot, or flashes when turned on (Gigabyte AB350 Gaming 3)

[Daniel Thomas]

Before I explain what's going on with my system I'll list my system specs, and the troubleshooting steps I've already taken to try and resolve this issue.

System Configuration:
Gigabyte AB350 Gaming 3 MOBO
Ryzen 5 1600 OC'd (3.7 ghz)
Zotac Mini Nvidia GTX 1070 OC'd (Don't remember exact settings)
Kingston Hyper X Fury 2400Mhz DDR4 16GB's
Powerspec 650W semi modular power supply
256GB M.2 SSD (Don't remember exact manufacture)
Inland 480GB SATA SSD
WD Blue 1TB 7200 RPM HDD

The troubleshooting steps I've tried so far(Not in exact order):

• Powering off system for about a minute, PSU switched off. Turning back on
• Reseating PSU MOBO power connector, CPU power connector, GPU power connector
• Reseat fan and CPU fan on pins.
• Tried booting PC without fans plugged in, excluding CPU fan. (I have a rear slotted fan connected directly to PSU connector)
• Tried reseating GPU into other PCIE slot
• Tired different wall outlets
• Tired with different PSU
• Removing PSU power, Removing CMOS battery, letting system sit for about 5 minutes, clearing CMOS pins. (Repeated a few times so far)

So yesterday I was on my PC like normal when I decided to add some old fans I had laying around into my case. This was probably one of the worst mistakes I could have made on my part. Not only did the fans not work (I only managed to try one before the problem started, and I do remember removing them previously because they suddenly stopped operating properly awhile back), but after installing the first fan my PC would no longer even boot sometimes. Components powered up, fans will spin, LED's will light up, but it won't POST. I tried all day yesterday to get it to POST once, but alas I had no luck. Until suddenly my PC wouldn't power on at all.

So at first this lead me to believe that maybe it was the PSU, so I pulled out a spare PSU I have laying around, and hooked it up to my MOBO, CPU, and GPU. When I switched it on, and pressed the power button on my case, still.... nothing. I hooked my other PSU back in, and tried further troubleshooting, and yet no difference. I was getting to the end of the night, so I decided to just give it a break. So I left the PSU switched flipped on, and left my PC be for the night. This afternoon when I woke up this is when this got interesting. I thought maybe letting it rest will allow any residual charges in my components to dissipate, and then perhaps my PC will work as normal. To a degree I was right. I press the power button on my case, and all of my components actually came back on again... finally. It briefly shut back off for a few seconds, and then came back on again, preceding afterwards my PC finally POSTed!

However, its not over. It was about maybe 5 or so minutes after I left and then came back to my PC when I decided, everything looks normal, I guess I'll put my side panels back on right? As soon as I did that all of a sudden my display went blank, my keyboard LED's shut off, and nothing was responsive. Oddly enough everything was still powered on like nothing happened at all. I tried powering the system off, but no matter how long I held it for it wouldn't shut off. So I had to flip the physical switch on my PSU to get it to turn off. I flipped the switch back on, and tried turning the system on again, the PC came on. This time it took about 8-10 seconds for me to hear the POST beep from the system, followed by the actual POST screen on my display, but then to my surprise the screen just starts flashing from POST screen to W10 log in screen. I shut my computer back off, this time with the case power button again as it worked this time. Turned it back on, and I hear the POST beeps, but there's nothing on the display. I'm thinking, "ok, maybe its just my GPU isn't seated properly from when I tried using the other PCiE slot". I took it out, reseated it, and now my system won't power on again.

I'm not quite sure what's going on here. I researched some stuff about my MOBO, and it seems that this model is known for having a "soft bricking" problem. I don't think its my GPU because I've had it for just about a year now. I got it second hand, but the guy I bought it from had it for less than a year. My PSU I got clearance at Micro Center, so I'm not entirely sure if there's something wrong with it either. Especially since my other PSU won't get my system to boot either. Of course, I haven't tested them on another system yet, so I don't know for sure. Which leads me to believe that my MOBO is the problem here. I'm trying so more things too at the moment. I've taken the PSU power and CMOS battery out, and allowed the system to sit for about an hour an a half now. I'm going to try booting with only one stick of RAM, and bare minimum fans plugged in to see what happens. Its kind of odd to think that this whole thing started from trying to add another fan back into my system. If anyone else have any idea of what's going on, and how I could possibly fix this it would be appreciated.

 

[Daniel Thomas]

UPDATE So I tried booting my PC with bare minimum stuff connected, and still didn't work. As a matter of fact I discovered that for some reason the power button won't even turn my system on anymore. However, when I short the power pins with a screwdriver it boots! Not only does it boot, but so far its been about 5 minutes and I haven't seen any flashing. I'm not sure why the power button isn't working any more though.

Here's the interesting part. I boot into the BIOS, and check some of my fan settings. My MOBO has an option in the menus that will tell you if your fans are failing. I checked the 1st fan, and I get a warning, but here's the thing... there isn't a fan connected to these pins, and this was the same pin I tried that fan in. So I'm trying to figure a way I could fix this warning. Maybe those pins have something on them that's triggering the alarm or something. I'm going to try and clean the to see what happens.