PC will not boot

[budui]

Hello,

I built a PC in January earlier this year with the following specs: Intel i5-12400F, Corsair Vengeance 2x16GB DDR4 3200MHz, MSI VENTUS 3X OC RTX 3070, ASUS B760M AYW WIFI DDR4, MSI MAG A650BN. Until around a month ago, the PC was working fine with no issues. However, now when the power button is pressed, the lights on the button flash constantly, about twice every second. The RGB turns on, and the fans spin. This however keeps on going, and the PC will not boot. The only way to turn the PC on was to repeatedly turn it on and off for around 15-20 minutes. Once turned on though, the PC ran perfectly fine, with no issues. Now the PC will not turn on at all, even after 2 hours of attempts, with the RGB and fans repeating the same behaviour. I am just wondering what the issue is, cause I have removed the GPU and RAM, and reset the CMOS, and yet the PC still doesn't run.

[BetteBalterZen]

When the PC is turned on but is not posting, do you see any LEDs lit up on the motherboard? I'm thinking of the debug LEDs. 

Example pic: 

[leclod]

You have no integrated gpu so you need the gpu

and you need ram

But remove the unnecessary, rgb, fans

Edited August 15, 2025 by leclod

[budui]

4 minutes ago, BetteBalterZen said:

When the PC is turned on but is not posting, do you see any LEDs lit up on the motherboard? I'm thinking of the debug LEDs. 

Example pic: 

I don't think I have debug LEDS on this motherboard

[BetteBalterZen]

3 minutes ago, budui said:

I don't think I have debug LEDS on this motherboard

Oh what the hell, yeah, just looked at a photo of your motherboard and it seems like there's no debug LEDs... Huh, thought that was default on all motherboards. Do you have a beep speaker? 

[leclod]

3 minutes ago, budui said:

I don't think I have debug LEDS on this motherboard

you kind of do

[budui]

4 minutes ago, leclod said:

you kind of do

Slow blinking on the power button, about one second light on, one second light off

[leclod]

3 minutes ago, budui said:

Slow blinking on the power button

could be gpu or boot device

does the display do anything ?

do you have another drive or can you try to reinstall windows ?

Edit : you probably meant gpu, 

Edited August 15, 2025 by leclod

[budui]

Just now, leclod said:

could be gpu or boot device

does the display do anything ?

do you have another drive or can you try to reinstall windows ?

Nah but once the PC actually boots everything runs without any issues

[leclod]

1 minute ago, budui said:

Nah but once the PC actually boots everything runs without any issues

I'd say the psu is guilty but difficult to know for sure...

[budui]

11 minutes ago, leclod said:

I'd say the psu is guilty but difficult to know for sure...

I don’t have much time on my hands but I’ll try ask a friend for a spare PSU so that I can test out your theory

[budui]

Also I don't know if this provides any more detail, but if I put the PC to sleep, and then try waking it up, the display doesn't show anything, but the RGB lights up, and the fans start spinning.

[leclod]

3 minutes ago, budui said:

Also I don't know if this provides any more detail, but if I put the PC to sleep, and then try waking it up, the display doesn't show anything, but the RGB lights up, and the fans start spinning.

I never use sleep & co, I turn off.

Does your issue persist if you turn off ?

[budui]

7 minutes ago, leclod said:

I never use sleep & co, I turn off.

Does your issue persist if you turn off ?

Yeah same thing then I have to repeat the process of turning the PC on and off until it hopefully boots 

[budui]

I'm going to test out a friend's GPU and I'll update on the situation

[budui]

I've tested my friend's 1650 super, and there is a red light on it. Same problem persists

 

[MLG_15]

My guess is that it’s a PSU issue. These intermittent problems can be hard to diagnose. Could you try using a different power supply?

[budui]

2 minutes ago, MLG_15 said:

My guess is that it’s a PSU issue. These intermittent problems can be hard to diagnose. Could you try using a different power supply?

I don't have the time for that so I'll probably just buy a new one and see how it goes

[budui]

I tried the paper clip test with a wire, and nothing happened, so the psu is probably fried

[MLG_15]

7 hours ago, budui said:

I tried the paper clip test with a wire, and nothing happened, so the psu is probably fried

The paper clip test does not provide much insight, as the PSU could be on but the fan may not spin unless the temperatures rise.

Voltages and consistency could still be off, and without proper measurement equipment, it's impossible to pinpoint exactly what's failing.

Try a new PSU and see what happens, it might also be worth checking if the warranty is still available.

 

 

P.S. You might want to check out LTTLabs PSU tests. Personally, I’d recommend going with a Seasonic or Corsair

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