[SOLVED] PSU or Motherboard Problem?

[FrozenGhost89]

My pc build is as follows: Asus Z97 wifi ac motherboard, core i5 4690k processor, 16 gb of RAM, 250 GB samsung ssd 860 EVO, WD Blue 2TB hard drive and seasonic 750 prime gold psu. My problem is that my pc doesn't start when I press the power button. The motherboard onboard power button turns on but nothing happens if I press it. The LAN light also turns on but no fans or other lights turn on. Then around 15-20 minutes later, sometimes longer when I press the case power button suddenly the pc boots up and runs fine with no problem. I kept the pc on for nearly 72 hours before shutting down and the performance was completely normal. But as soon as I shut down my pc it couldn't start again for nearly 45 minutes. Do you think the motherboard is at fault or the power supply?

 

[Lutfij]

Welcome to the forums, newcomer!

When posting a thread of troubleshooting nature, it's customary to include your full system's specs. Please list them like so:
CPU:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:
Monitor:

You might want to source a donor PSU and see if you're able to get the system to POST and then into BIOS. You forgot to mention the make and model of your discrete GPU. Also, how old is the PSU listed above? Do you feel a mild tingling sensation when you touch the exterior of your chassis while your feet are making contact with a non carpeted (non wooden)tiled floor?

 

[FrozenGhost89]

Welcome to the forums, newcomer!

When posting a thread of troubleshooting nature, it's customary to include your full system's specs. Please list them like so:
CPU:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:
Monitor:

You might want to source a donor PSU and see if you're able to get the system to POST and then into BIOS. You forgot to mention the make and model of your discrete GPU. Also, how old is the PSU listed above? Do you feel a mild tingling sensation when you touch the exterior of your chassis while your feet are making contact with a non carpeted (non wooden)tiled floor?

Thanks for replying quickly. I don't feel a tingling sensation when I touch my pc. Also my pc currently doesn't have a graphics card. I am relying on intel graphics.

 

[FrozenGhost89]

CPU: Intel Core i5 4690K
Motherboard: ASUS Z97 wifi ac
Ram: 16 GB Corsair
SSD/HDD: Samsung 250 GB 860 EVO/ 2 TB WD Blue
GPU:None
PSU:Seasonic 750 prime gold
Chassis: Corsair Carbide 500r
OS: Windows 10
Monitor: Dell U2414H

 

[FrozenGhost89]

CPU: Intel Core i5 4690K
Motherboard: ASUS Z97 wifi ac
Ram: 16 GB Corsair
SSD/HDD: Samsung 250 GB 860 EVO/ 2 TB WD Blue
GPU:None
PSU:Seasonic 750 prime gold
Chassis: Corsair Carbide 500r
OS: Windows 10
Monitor: Dell U2414H
My problem is that my pc doesn't start when I press the power button. The motherboard onboard power button turns on but nothing happens if I press it. The LAN light also turns on but no fans or other lights turn on. Then around 15-20 minutes later, sometimes longer when I press the case power button suddenly the pc boots up and runs fine with no problem. I kept the pc on for nearly 72 hours before shutting down and the performance was completely normal. But as soon as I shut down my pc it couldn't start again for nearly 45 minutes. Do you think the motherboard is at fault or the power supply?

 

[Lutfij]

Is this the board you're working with? You forgot to answer the other question I had. Breadboard the system and with bare minimum parts, see if you get POST. Link to your ram kit used?

 

[FrozenGhost89]

Is this the board you're working with? You forgot to answer the other question I had. Breadboard the system and with bare minimum parts, see if you get POST. Link to your ram kit used?

Yes it is the motherboard I have. My RAM is Corsair 16 GB. The link is here https://www.corsair.com/us/en/Categories/Products/Memory/VENGEANCE®-Pro-Series-—-16GB-(2-x-8GB)-DDR3-DRAM-1866MHz-C9-Memory-Kit/p/CMY16GX3M2A1866C9.
My PSU is 3 years old.

 

[Bazzy 505]

My pc build is as follows: Asus Z97 wifi ac motherboard, core i5 4690k processor, 16 gb of RAM, 250 GB samsung ssd 860 EVO, WD Blue 2TB hard drive and seasonic 750 prime gold psu. My problem is that my pc doesn't start when I press the power button. The motherboard onboard power button turns on but nothing happens if I press it. The LAN light also turns on but no fans or other lights turn on. Then around 15-20 minutes later, sometimes longer when I press the case power button suddenly the pc boots up and runs fine with no problem. I kept the pc on for nearly 72 hours before shutting down and the performance was completely normal. But as soon as I shut down my pc it couldn't start again for nearly 45 minutes. Do you think the motherboard is at fault or the power supply?

The way it works, on poweron signal, ATX spec calls for voltage to reach spec within certain time, if that happens powerok signal is sent and fans spin up and all the other good things start happening.

It seems your PSU has aged to the point, that it's falling out of relevant ATX spec. I would suggest replacing it.

Some may rush in a suggest replacing cmos battery on motherboard, but this behavior hardly warrants it. CMOS batteries these days do nothing more than maintain RTC.

 

[FrozenGhost89]

The way it works, on poweron signal, ATX spec calls for voltage to reach spec within certain time, if that happens powerok signal is sent and fans spin up and all the other good things start happening.

It seems your PSU has aged to the point, that it's falling out of relevant ATX spec. I would suggest replacing it.

Some may rush in a suggest replacing cmos battery on motherboard, but this behavior hardly warrants it. CMOS batteries these days do nothing more than maintain RTC.

Can you be absolutely sure that the motherboard is fine and this seems to be only a psu problem?

 

[Phillip Corcoran]

Can you be absolutely sure that the motherboard is fine and this seems to be only a psu problem?

It's impossible to be "absolutely sure", such is the nature of PC troubleshooting.

 

[FrozenGhost89]

So, I got a psu tester and plugged in my motherboard 24 pin connector into it. When I turned it on all Led lights glowed except for the - 5V light. Does this indicate a problem with the psu?

 

[FrozenGhost89]

So, I got a psu tester and plugged in my motherboard 24 pin connector into it. When I turned it on all Led lights glowed except for the - 5V light. Does this indicate a problem with the psu?

Can someone please help me? I need to give an exam on Monday which will be conducted online. So I need my pc for that.

 

[Bazzy 505]

So, I got a psu tester and plugged in my motherboard 24 pin connector into it. When I turned it on all Led lights glowed except for the - 5V light. Does this indicate a problem with the psu?

-5 voltage (used to be pin 20) has been phased out from atx standard in late 90's, you only need to power ISA slots. That's some really vintage tester you got there, certainly not a reliable way to test modern PSU

those led 12 buck testers can for the most part only tell you if PSU is completely dead, but can't really tell you if its good

 

[FrozenGhost89]

So I checked my psu in another pc and that pc booted up perfectly well with no problems at all. But in my pc I still can't get my pc to post until atleast 30-40 minutes are gone, sometimes longer. So I think it must definitely be the motherboard at fault. Does anyone have any idea as to what could be the problem?

 

[FrozenGhost89]

So I checked my psu in another pc and that pc booted up perfectly well with no problems at all. But in my pc I still can't get my pc to post until atleast 30-40 minutes are gone, sometimes longer. So I think it must definitely be the motherboard at fault. Does anyone have any idea as to what could be the problem?

Can somebody please help me out?

 

[FrozenGhost89]

Can somebody please help me out?

Is there anybody there?

 

[Satan-IR]

I think it's a more likely to be a PSU issue too.

Usually a sign a PSU has been going bad gradually is it takes a long time for the PSU to to respond from standby mode and and the system to POST.

See if you can replicate the PSU turning on immediately on your own system by turning it off with it's own switch or unplugging it for a while from wall outlet. See if it starts faster after power is cut for a while.

Anyway (if possible) I suggest you test your system with that other PCs PSU too if haven't already done it. If other PC's PSU turn your system on as it should upon pressing the button I'm affraid you need to raplace your PSU.