Question PC suddenly not booting - Display not detecting any signal either

[RoystonButhello]

I'll try my best to detail the actions leading up to the incident and the issue itself.
Edit: I should mention that I've been using the SSD as a secondary drive for the past month with no issues; there are no problems with the drive itself or its installation.

System:
CPU: i7 4790K
Mobo: Gigabyte Z97-X Gaming 5
RAM: 2x8 1600MHx HyperX Fury Modules
HDD: Seagate Barracuda 2TB 7200RPM
SSD: WD Green M.2 240GB

Actions leading up to the issue and attempts at resolving it:-

1. Cloned HDD to SSD with Acronis True Image WD Edition to migrate OS
2. Was unable to boot via SSD's boot manager, but was still able to boot to Windows via the HDD's boot manager.
3. Plugged in USB with Windows 10 installation media and unplugged HDD to do a fresh install of Windows 10 on the SSD instead
4. On pressing the power button, all fans start spinning and all LEDs and USB devices except the Keyboard and mouse are visibly receving power
5. However the monitor isn't picking up a signal from either the GPU or iGPU, I tried a second cable to confirm that it wasn't the cable at fault
6. The "Reset" button on my case that's hooked up to the motherboard that forcibly restarts the computer isn't working
7. Unplugged all drives , force shut down the system and started it up again - same result
8. Tried draining the CMOS battery via the jumpers on the motherboard - same result
9. Tried draining the CMOS battery (removed it, unplugged the PSU, then held the power button for a few seconds before reinserting the battery) - same result
10. Attempted booting with the Insert key held down - no effect since keyboard LEDs aren't lighting up; keyboard presumably isn't even active

Regarding the keyboard and mouse, I found that if after starting up the system I plugged them into a different USB port they'd start receiving power. However the next time I tried starting up the system they would fail to receive power from that port. along with any other ports it was connected to since the onset of this issue.

I have no idea what's happening, what caused it and what I can do to resolve it. I've looked around several forums to no avail, I'm at a complete loss. Any help is very much appreciated.

 

[rocktalkrock]

Your M.2 SSD and Sata HDD could be conflicting. Try switching your HDD to a different Sata port.

(M.2, SATA Express, and SATA3 4/5 connectors can only be used one at a time. The SATA3 4/5 connectors will become unavailable when an M.2 SSD is installed.)

 

[RoystonButhello]

I made sure to avoid that issue when installing the SSD. In fact I've been using it for a few applications and games for the past month so I can confirm that it isn't the issue.

And to reiterate one of the solutions I tried, I disconnected both my SSD and HDD and started up the PC but the monitor still didn't pick up a signal from either the GPU or iGPU, and my keyboard and mouse aren't visibly receiving power.

 

[rocktalkrock]

Double check both sticks of RAM are still seated properly in their slots.
Double check all the power cables from your PSU.

 

[RoystonButhello]

Just reseated my RAM and tried turning it on, but this has brought up a new issue.
The computer starts up, the fans start spinning and the LEDs turn on, then it shuts itself down after 7-8 seconds and immediately starts back up again, and repeats this behaviour ad nauseam.

I cleared the CMOS battery and double-checked all my cables, reseated my RAM again, and tried starting it up with the GPU, HDD and SSD disconnected and it still exhibits this on-off cyclical behaviour. Also the issues from before remain - my monitor still isn't receiving video signals from my PC, the restart button hooked up to the motherboard does nothing and my Keyboard and mouse never receive power.

My best guess is my motherboard is borked and reseating the RAM somehow aggravated whatever issue it decided to have earlier today.
Either that or my PSU is somehow to blame, which may be possible since it had an issue last year that prevented it from turning on. I had it repaired but it's the only one of my components that's failed in the past 4 years, which gives me a bit of a reason to suspect it.

Any ideas or suggestions from your side?

 

[rocktalkrock]

What is the power supply, is it a good quality brand? Have you checked all the power sockets and RAM slots are clean, no dirt, lint or pet hairs?

 

[RoystonButhello]

The power supply is a Corsair CX 750M 80+ Bronze certified PSU.

When double-checking the cables I made sure to check for any gunk that may have found its way into the sockets. Everything checks out on that front.

 

[rocktalkrock]

All i can suggest is to strip your system down to the fewest parts possible to get into the BIOS. Use the onboard graphics, one stick of RAM (try both) and no drives. You could also try booting your motherboard outside the case.

 

[RoystonButhello]

Welp, I'm afraid I've already tried that. The only thing left is booting the board outside the case. I'll give that a shot tomorrow (it's ~11PM here).

In the event that it doesn't work should I just take the board to a PC hardware or repair store and have someone test it out with another set of parts? I feel almost certain that somethings gone screwy with the board that's beyond what I can do to fix it, unless there's more I could possibly do on my part.

 

[rocktalkrock]

I'm not aware of any computer shop that tests old motherboards. The time, and therefore the cost of testing the motherboard would be better spent on a new board.

 

[lmacmil]

I'll try my best to detail the actions leading up to the incident and the issue itself.

I have no idea what's happening, what caused it and what I can do to resolve it. I've looked around several forums to no avail, I'm at a complete loss. Any help is very much appreciated.

I have nothing to offer solution-wise but am sympathetic since I've just gone through a similar situation. System is Asus B150M mobo, booting from M.2 SSD and running fine with 2x4GB. I had 2x4GB of same brand RAM but different speed and timing so I put them in to see if it would run. Wouldn't even turn on. Removed them and still wouldn't turn on. No lights, no beeps, nothing. Decided it must the the PSU (I have had recent occasional issues where it wouldn't turn on but always did eventually) so I swapped it. Now it turns on but I have no video from either the Intel on-board graphics or a known good PCI card. I don't know if it's possible for a PSU failure to kill the motherboard graphics but at this point I don't know what else it could be. OTOH, it's an excuse to upgrade mobo and CPU to 8th generation hardware.

The joys of DIY computers!

Edit: discovered my problem! Turns out if one of your DIMMs is not fully seated, the PC will start but there will be no video. It helps if you have sufficient light inside the case to see what's going on!

 

[gn842a]

I wear one of these when I'm working on a PC.

I find that even if I have bright light in the work area (which I do), when I stick my head into the case the shadow of my own head often makes it difficult to see what's going on. The head lamp doesn't have to go through my head.

Glad you found the problem. GN

 

[lmacmil]

I wear one of these when I'm working on a PC.

I find that even if I have bright light in the work area (which I do), when I stick my head into the case the shadow of my own head often makes it difficult to see what's going on. The head lamp doesn't have to go through my head.

Wow, that's pretty cool. Never even thought of a headlamp before. Sure beats trying to hold a Maglite in your teeth!

 

[RoystonButhello]

I'm not aware of any computer shop that tests old motherboards. The time, and therefore the cost of testing the motherboard would be better spent on a new board.

I do personally know the repair guys and get along with them rather well, so I'll see if they can do me a favour and just do some simple tests to assess the board's condition.

If it's beyond hope or if the repair costs are expected to cross a certain amount, I may as well just throw in the towel and try to sell my CPU and RAM. It's the best reason I have to finally upgrade to an 8th gen system.

Regardless, thanks for all the suggestions! And if nothing else I've at least grown reaccustomed to tearing apart and putting back my rig. It's been years since I had to do anything beyond replacing a single part.

 

[RoystonButhello]

Sure beats trying to hold a Maglite in your teeth!

And here I'd settled for using bits of my case to creatively angle my phone's flashlight where I needed it.