New build power cycling endlessly after working for 12ish hrs

NurseNessa73

Commendable
Oct 17, 2016
2
0
1,510
Hello! I am having an issue with a recent build of my computer. I am new to building my own computer. These are the components I have:

CPU: Intel Core i3-6100 LGA1151
Motherboard: Gigabyte GA-H110M-A Micro-ATX LGA1151
RAM: G.SKILL NT Series 16GB (2x8GB) Dual-Channel Kit DDR4 2400MHz
Video Card: Radeon RX 460 4G
Storage: Seagate ST1000DM003 1TB 7200rpm
Optical Drive: ASUS 24X SATA DVD Burner
Power Supply: EVGA 430W 80+
Case: SilverStone PS08B Micro-ATX
OS: Windows 10 Home

Nothing fancy, just a budget gaming/general purpose PC. I got the build from here: http://www.hardware-revolution.com/best-low-cost-budget-gaming-pc-september-2016/
It's a Tier 2 build.

I'm going to give the long version of what happened and what I've tried to see if anyone can help. So I got all my parts and followed a guide and got everything together. My husband helped me a bit with the first couple things like installing the CPU. When he took the CPU fan out of the box, he accidentally smeared a very small portion of the thermal paste, but everything looked good. I put all the components in and it started right up. Brought it to my monitor (which was still attached to my current computer), and saw quickly that it was POSTing to BIOS. I installed the optical and hard drive and then installed Windows. It was running great and I let Windows activate and went to bed. The next day, I was using the included disks to update graphics driver and some utilities for the motherboard. I did NOT update the firmware for the motherboard. I had to go do something, so I left the computer to restart after it finished updating the GPU driver. At this time, the computer had been up and running for 12 hrs. While checking things out, I had noticed under the System display in Windows that it said I only had 8 GB RAM, but I know I installed 16. Later that day I came back to my computer to check it and it was off. I figured since it was off, I would make sure that both sticks of RAM were seated correctly. I unplugged the system and made sure to discharge static to the best of my ability, and checked both sticks by removing them entirely and reseating them. Put everything back together and powered it up. Suddenly my system was power cycling endlessly after approx 15 secs. I could not turn it off fully using the power switch on the case and had to use the switch on the PSU. This behavior continued, although intermittently, the power switch on the case sometimes just wouldn't work either. If left running, it would just continue power cycling every 15 secs. I let it run for about 30 minutes at one point with no change in behavior. It never reaches BIOS that I can tell.

Trouble shooting steps taken:
I tried many things including removing each stick of RAM and trying it in either slot with the same behavior, as well as checking power cable connections and every other recommendation for failure to POST that I could find.
I slowly removed each component and tried it and it continued to power cycle until I removed the CPU. Without the CPU it would stay powered on and would turn off with the power switch on the case. We inspected the CPU socket and there was 1 bent pin. Believing we had diagnosed the issue, we bought the same motherboard and replaced it, using new thermal paste after removing the old. With only the new motherboard and the CPU, the issue still occurred. At that time we assumed it was the CPU. Sent it back and got the replacement on Friday. Just put everything back together (just new motherboard and new CPU + RAM), and the issue still occurs. Still happens if RAM is removed. My old/current computer has a PSU with the same specs, so I tried powering it up using that PSU as I know that it works. The issue still happens. I have noted that even after switching off the PSU by it's power switch, the motherboard still attempts to turn on with any residual power. Oh, and I do not have a case speaker so there is no beeps :)

At this point I am baffled. I don't know what the issue might be or what my next step is. Can anyone see anything I have missed? My only other idea is to take it into a shop for someone to look at it.
 

NurseNessa73

Commendable
Oct 17, 2016
2
0
1,510
Not sure what's different, but I picked up a case/motherboard speaker (and some new RAM, just in case it was that), only new thing I plugged in was the case speaker and it booted up fine. I am actually posting from my new build. *shrug*