Question System Gone Goober | What's Happened To It?

[HelloGorilla]

Never thought I'd be one of those 'makes Toms hardware account because his system mysteriously borked out' kinds of people, but here I am anyway. Here we go from the top, but here's my specs for reference:
Mobo: EVGA Z170 Stinger
CPU: i5-6600k
PSU: EVGA Supernova 750 G2
RAM: Kingston HyperX 2133mhz DDR4 8Gx2
GPU: RX480 8GB
OS: Windows 10

I've been with my current system for the better part of 2.3 years. Yesterday however, as I was playing Quake Champions (don't play it and BUY 'DIABOTICAL'), my screen suddenly turned black. The PC itself was still running however, as I could clearly hear the in-game sounds. I checked to make sure it wasn't a display port issue, and it wasn't. Tried all button combinations to get it respond, but nothing was working. I've got a EVGA Z170 Stinger motherboard, so I tried jumping into the BIOS by hitting the Clear CMOS button. Problem was, I couldn't access the BIOS. I'd be spamming F12 and other appropriate keys, but it just wasn't having it.

The PC was still restarting fine, however I noticed that the motherboard splashscreen was no longer coming up. It would go straight to the very cheap looking windows loading bar and boot to desktop. Obviously I found it weird that I couldn't access the BIOS, so I figured I'll just install the latest BIOS firmware. I downloaded the latest BIOS driver from EVGA website, and installed it after downloading. When the PC reset, that was that.

It would no longer boot to BIOS, let alone past it (edit: aka doesn't post).The LED kept cycling through a few post codes, hanging on 4C at the end for a few seconds, and repeating the cycle. Checking the post code on the manual wasn't helpful, and so I began searching up the issue on the internet. As those already in the know, the 4C post code isn't something specific, but it means something is definitely wrong. Reading through existing threads, I tried a number of things:

-Taking out mobo battery for over an hour,
-Taking out the GPU and trying to boot with just CPU and RAM,
-Trying the above but with just one RAM (alternating through both slots),
-Trying different RAM.
-Check the CPU throne for bent pins (there are none).

The different RAM I tried was from a friend. They were GSKILL 3000mhz DDR4 8Gx2. I was running the HyperX Fury 2133mhz DDR4 8Gx2. He agreed to swap with me for a couple of hours so I could guarantee it wasn't a RAM issue. My RAM was working on his system fine, and I was still getting the same issue on my board with his only 1 month old RAM.

This is when I decided to pull everything out and try again. Here's what it looks unpowered (note only the CPU and mobo power cables are plugged in):

https://imgur.com/AWmO9Zx

View: https://imgur.com/AWmO9Zx


Here's what I get when I power the mobo without RAM:

https://imgur.com/ItdrQPJ

View: https://imgur.com/ItdrQPJ

It cycles through a few postcodes and hangs a little longer on 53 (meaning no usable memory is detected, which is fine).

And here it is when I add in a single RAM stick into slot 1:

https://imgur.com/2Z4HMvc

View: https://imgur.com/2Z4HMvc

Once again, it cycles though a number of post codes and hangs at 4C for a little longer.

It's at this point that I decided to make a thread just to get some outside opinion. I find it unlikely that the PSU is the culprit, even more so that the BIOS update would ruin the mobo like this, but what the hell do I know. For whatever reason, it feels like the motherboard went insane (for whatever reason), and isn't recognizing/reading the RAM.

Thank you for your time, and I hope to hear your thoughts.

 

[boju]

Bit of a doozy

Saw this video, though it says C as the error code (not in the manual) could it be similar? Bit strange how 4C isn't in the manual either, that's silly.

Wondering if it could be the Displayport cable. Seeing your motherboard also has Displayport have you tried Hdmi?

 

[boju]

I reread your post and seen you tested Displayport cable, was that just checking connection or different cable altogether?

C relates to a grounding issue, 4C might not be grounding exactly or could it?

 

[boju]

EVGA Z170 Stinger debug code 4C, 19 & C

Doesnt POST. Debug LED only keeps repeating these codes 4C & 19 (sometimes C). History Previous issue was only error debug C. Other people was able to resolve the issue by changing PSU. So I did. From Corsair VS450 to Seasonic M12-Evo. Now it's giving me a different error code...

forums.tomshardware.com

This person had 4c, ended up being crook ram. But you're able to boot unlike them. Thought id share it (if you haven't seen already) and try another stick of ram. When you tested one stick did you try the other stick as well?

 

[HelloGorilla]

EVGA Z170 Stinger debug code 4C, 19 & C

Doesnt POST. Debug LED only keeps repeating these codes 4C & 19 (sometimes C). History Previous issue was only error debug C. Other people was able to resolve the issue by changing PSU. So I did. From Corsair VS450 to Seasonic M12-Evo. Now it's giving me a different error code...

forums.tomshardware.com

This person had 4c, ended up being crook ram. But you're able to boot unlike them. Thought id share it (if you haven't seen already) and try another stick of ram. When you tested one stick did you try the other stick as well?

I think I need to clarify what I mean by boot. I can power on the mobo, but that's it really. I can't get past the 4C issue - I don't even have the GPU plugged in since there's no point. Indeed I've already seen both the thread and the video you posted earlier, but I've already tried different RAM on my system (same issue) and tried my RAM on a different system (works fine). Yes, I've tried one stick at a time as well.

Also thanks for responding man, I really appreciate it.