Question Fails to POST, then tries again...

Aug 10, 2020
4
0
10
Hey all,

Recently, my machine has begun to fail to boot properly. Built it 5 years ago, haven't really touched the insides since -- this problem seemed to come straight out of the blue.

What usually happens is when the power button is pressed, the button's LED turns on, CPU + PSU fans start spinning, but then stop about 2-3 seconds later. After a pause, this repeats until I shut the PSU off. This problem first occurred about 4 months ago. To attempt to solve it I tried replacing the PSU, but that didn't fix things. Only after a CMOS reset did it seem to magically work again, and the problem seemed to go away..

Recently, the repeated boot failure cycle has come back. At first, clearing the CMOS every time got it up and running, but it's gotten less and less consistent. Sometimes, unplugging the PSU, waiting, plugging it back in, seeing if it turns on for more than a second, and repeating leads to an eventual flawless boot. I've also found that leaving the computer unplugged overnight tended to mean it would turn on smoothly in the morning, whereas leaving the PSU on resulted in the problem appearing more often (but honestly, that feels a lot like superstition in hindsight.)

The computer hasn't been able to turn on for two days now. I've gone through all of The Checklist (besides breadboarding just the motherboard... I know, I plan on doing it in the morning if all else fails) The only thing that seems plausible to me is that the problem lies somewhere with the motherboard, but I feel very out of my depth trying to diagnose an issue that could arise from so many sources. I'm just wondering if anyone's got any advice from a similar experience, perhaps with similar parts. Thanks!

Specs:
MOBO: ASUS Z97-AR
PSU: Corsair CX 750M
CPU: Intel i5-4690
GPU: ASUS TURBO GTX970-OC-4GD5
HDD: WD Blue 1TB
SSD: Toshiba OCZ TL100
RAM: Crucial Ballistix Sport 8GB DDR3
Case: Thermaltake Versa H21
 
Aug 10, 2020
4
0
10
I have no pixie dust for you, only my 2 recent Z97 fails that are similar. I don't think any other part is relevant (except psu) when you can't even get a post. But I do wonder what goes on when mobo is put to sleep. What is yr OS? Z97 good board new but many parts 5 y/o now. Might be tempting to buy a replacement Z97, as I did. Wrong. 😢

Using Windows 10 64bit here, based on your experiences too it seems like the mobo is the likely culprit. Taking the plunge and upgrading the aging parts seems to be the way to go 😪
 
Aug 10, 2020
4
0
10
Following up, ended up having to replace the motherboard (Along w/ changing out the RAM and CPU). Doesn't narrow down the culprit much, but all works fine now.