[SOLVED] Will PC power on without a cpu cooler?

Apr 4, 2020
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I'm having problems and I've narrowed it down to either a mobo or cpu problem. It turns off for less than a second then turns off. I've tried multiple good psus. BUT I just thought of one thing. Will not having a cpu heatink installed cause this? I'm just trying to get POST.
 
Solution

now that you have the needed parts, you can troubleshoot. this usually covers most new build gremlins. go down the list every step, step 17 is important, the motherboard will help if you know how to listen.

you can bodge together a speaker for testing and buy a dedicated speaker later.
they used to come with every case and motherboard.

canned diagnostic speaker rant: speaker making 101
The diagnostic speaker is the motherboards main diagnostic feedback device.
the motherboard may be telling you where the problem is.
my speakers have this plug...
I remember once, I had a thunderbird core AMD and I forgot to put the cooler on, I hit the power and the chip died right there and then.
luckily since that oopsie they have thermal switches that shut them down rather than letting them die.

use the cooler.
 
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I'm having problems and I've narrowed it down to either a mobo or cpu problem. It turns off for less than a second then turns off. I've tried multiple good psus. BUT I just thought of one thing. Will not having a cpu heatink installed cause this? I'm just trying to get POST.
MOST motherboards monitor the CPU fan. If it doesn't get a valid RPM for the CPU fan it will shut down. That is a likely cause.
 
How quickly? I've had an aio installed. It did the same thing. I suspected it to be a bad aio because I've had to refill it in the past. That's why I took it off I don't want it to leak onto the cpu/new motherboard. When the power does after being on for a fraction of a second, I can feel the cpu continually getting hotter. Mobo is new and is a ga-z87-hd3 and i7 4770.
 
MOST motherboards monitor the CPU fan. If it doesn't get a valid RPM for the CPU fan it will shut down. That is a likely cause.

I've plugged in a case fan on the cpu_fan header just to make sure it doesn't do this. However, if I unplug the 8 pin eps, it powers on for a TINY bit longer, maybe 1 second, instead of a fraction of a second with the eps connector.
 
MOST motherboards monitor the CPU fan. If it doesn't get a valid RPM for the CPU fan it will shut down. That is a likely cause.
I remember when I forgot to plug CPU fan pins to the motherboard, PC turned on telling me to connect it, without letting me do anything but shutting it down. A great oopsie! 😆
 
Ok I'm going to buy one right now. Question, how does it know if there's no heatsink installed? Pressure? Or the rate of the rise in temperatures? In a fraction of a second?
 
Ok I'm going to buy one right now. Question, how does it know if there's no heatsink installed? Pressure? Or the rate of the rise in temperatures? In a fraction of a second?
Many motherboards require a tach signal from the fan to run.
So it "knows" you don't have a fan connected.
If you do have a fan connected....but the heat sink isn't in place....I think the CPU temp will skyrocket fast and I wouldn't be surprised if it shut down because of that.
 
I once tried to kill an Athlon 3200+ by toying around with various OCs and degrees of heatsink connection. I was able to run the CPU with the cooler on but no thermal paste, and the fan just sitting off to the side, but once I removed the heatsink from the CPU, the system thermally shut down almost instantly.

That was from the era (130nm process node) where thermal density wasn't much of an issue. Compare that to your 22nm 4770K or modern 7nm CPUs!!
 
So now I have a heatsink installed, it's doing the same thing when the 8pin EPS is plugged in. However, there's progress, if I unplug the EPS, it turn on for 3 whole seconds, instead of half a second. It also keeps rebooting, whereas it didn't before, power would just stop Any ideas?
 

now that you have the needed parts, you can troubleshoot. this usually covers most new build gremlins. go down the list every step, step 17 is important, the motherboard will help if you know how to listen.

you can bodge together a speaker for testing and buy a dedicated speaker later.
they used to come with every case and motherboard.

canned diagnostic speaker rant: speaker making 101
The diagnostic speaker is the motherboards main diagnostic feedback device.
the motherboard may be telling you where the problem is.
my speakers have this plug
http://images.crutchfieldonline.com/graphics/infolib/homelib/hSpeakerSpringClip.jpg
I use lamp wire but any stranded wire will do. literally any stranded wires. strip one end like so
http://www.antiquelampco.com/Shades/CordColors.jpg
attach the stripped end into the speaker spring clips on the speaker.
the other end of the wire should be trimmed like so the semi strip
https://wesbellwireandcable.com/images/cutwire.png
by doing a semi strip the wire case is now the socket.
plug one wire to the first pin, and the second onto the fourth pin.
power on the system and listen for beeps
end canned rant
 
Solution