PC won't turn on. Any advice before ordering new motherboard?

[TTD187]

Hello people,

A little back story about the faultiness of my PC.

So for some time, I would try to turn on my PC and it would tell me to select a proper boot device every now and then when turning it on (it was usually more common if I'd not turned the PC on for a longer period of time, maybe up to 12 or 24 hours). Whenever I restarted the PC, it would fix the issue and I'd go into Windows, play a few games and all that as I'd normally do.

Around a month ago, I went away for a few days and I turned off all the plugs in my flat so I wouldn't be wasting any energy. I was sure to make sure the PC was switched off before doing this, of course. So upon returning home after 4 days, I tried to turn on my PC and absolutely nothing occurred (don't worry, I'd made sure the power was on at the switch and PSU). I tried several times, doing different things without touching the insides of the PC, however, I wasn't getting any luck.

I decided that I should consider diagnosing the issue inside the PC. I removed the CMOS battery for a whole night, I tried to see if it was the power on switch by changing it with the reset button and shorting with a screwdriver. I tested both RAM sticks individually in each of the RAM slots. I tried to reseat everything inside the PC. I tried booting with and without the CPU installed, and after all that, nothing happened.

I tested the PSU with the paperclip test and it passed, but just to be sure, I decided to buy a PSU tester which read that all the voltages were fine, so I figured, that if it was the CPU at fault, the PSU fans should at least spin up upon turning it on, so I've come to the conclusion it's most likely the motherboard that's faulty.

I'm going to order a new H81M board today just to tide me over until I buy a more powerful and modern PC later in the year, but just would like to know if there's anything else I should go over.

Spec:

MSI Z97 G55-SLI
i5-4690k
2x4GB Kingston HyperX 1600Mhz RAM
GTX 1070 Ti
XFX Pro850W 80+ Bronze

Thanks!

 

[gdmaclew]

Your first problem was most likely the CMOS battery. It should have been replaced with a new one.

Why did you try to boot without the CPU? It will not POST without one.
Because you have 2 RAM DIMMS, you should be using only slots DIMM2 & DIMM4.

Before you went away did you switch the PSU off using its power switch? If so, did you remember to switch it back on?

 

[TTD187]

Your first problem was most likely the CMOS battery. It should have been replaced with a new one.

Why did you try to boot without the CPU? It will not POST without one.
Because you have 2 RAM DIMMS, you should be using only slots DIMM2 & DIMM4.

Before you went away did you switch the PSU off using its power switch? If so, did you remember to switch it back on?

I understand the CMOS dying causing the previous issues, but that would surely not cause the PC to not turn on.

The whole time my PC was working, the RAM slots were in DIMMs 1 & 3, but as I said, I tested with the individual sticks in each slot anyway to see if either the RAM or DIMMs weren't working.

I can't remember whether or not I switched off the power switch on the PSU, but I did mention that I made sure the switch was on when I returned (I switched it several directions just to make sure I wasn't being stupid).

The reason I tried booting without the CPU was just to see if that could be causing a complete lack of power on. I was clutching at straws at that point. I wasn't checking for POST, I was checking for power on considering nothing was turning on.

 

[gdmaclew]

I did not intend to suggest that a dying CMOS battery was the cause of your PC not turning on. I merely suggested it as a cause for your first problem.
The RAM and the DIMMS are the same thing. You probably meant the RAM or the slots, none of which would cause your PC to not power on.
The PSU switch has a 1 and a 0 on it to denote ON or OFF.
You were correct to test the PSU with a PSU tester because the paper clip test does not tell you if the correct voltages are available on the various pins.
You were right in assuming that if the CPU was faulty, it wouldn't stop the fans from spinning.
If there are are no lights illuminated on the motherboard then I would definitely suspect it as the cause.

 

[TTD187]

Ahh yeah, that would make sense. I always linked the two problems with each other as it did appear to be due to a lack of power running to the board for a certain period of time caused issues. It can make sense that the two are different problems entirely.

I've always referred to them as RAM sticks and slots. Always thought the DIMMs were the slots, but thanks for clearing it up for me.

I'm not the brightest spark sometimes. I have a tendency to be stupid in the simplest of situations, despite knowing what I need to know. It's why I tend to take precautions like that just to make sure I haven't been an idiot.

Sadly enough, my motherboard didn't come pre-equipped with lights or a speaker, so even if the board would power on, I wouldn't know the actual issue.

My guess overall would be power delivery to the board? Do you think overclocking the CPU could have caused it? I had put it up to 4.6Ghz (later 4.5Ghz just for increased stability at 1.29v (at 1.3v, the motherboard highlighted to voltage red, so I stuck away from reaching it). The temperatures never got particularly high. I believe they topped out at around 70-75 degrees (Noctua DH-14 cooler).