Hello everyone. 

I had my PC running this morning when it suddenly switched off. No programs running at the time. It was idle. 

I don't know if it was some kind of power surge/cut but when I tried to restart it, nothing happened. 

The green motherboard light is on as are the RGB motherboard lights. When I press the power button all I get is a "click" sound and nothing else. 

I tried a different power cord, connected to a different wall socket. I discharged the cappacitors by holding the power button while the PSU power button was in the off position. 

I built this system in 2020 and has been running fine since then. 

Is there any tests I can do to determine if it's "just" the PSU or something more serious like the motherboard or processor?

My PSU is a Corsair TX850M. 

Any help greatly appreciated. 

Hugo

 

Hmmm... what is 'supposed' to happen? Check you MB documentation and see what the green light means and any other diagnostics. What's your monitor doing? Is it booting off the SSD.. has that failed? Can you get into bios? Are the fans/cpu pump working? You seem to suspect the PSU but you have (some) power.

If you can't get your hands on a power supply tester, then your next best option is probably to try swapping in a different PSU to see if that fixes it.

The "click" sound you're hearing might be the relay in the protection circuitry on the PSU...if the PSU detects a short somewhere, it'll refuse to power the 12v rails, even though there may be power on the 5v standby circuit.  Check all your connections inside the case, and make sure there are no foreign objects or case components touching the motherboard (including and especially the back side).  I had a similar problem a while back that turned out to be a long untrimmed capacitor lead sticking out of the mobo's backside that was just barely touching the metal motherboard tray.

 

Thank you both for your input. 

@odourboy

The green light on the motherboard, according to the documentation, means the motherboard is getting power from the PSU. Regarding my monitor, it displays a "no signal" message. It doesn't get to the boot part and I can't get to the Bios because it doesn't turn on. Yes, there is some power but maybe not enough to "wake" the system? I don't know... 

@Bob Scott

I do have a Corsair HX650 PSU from a previous build. I don't know if it will be enough power but I can try for testing purposes. 

I am going to open my case again and check all the connections more thoroughly. 

The foreign objects theory is an interesting one. I"ll check for that too. 

Thank you again. 

Hugo 

It could be your RAM, try using just 1 stick at a time and see if your PC posts. I had one of my RAM sticks fail without warning and as a result my PC would not power on.

Could be a failed RAM stick.  In the failures to boot I have had, it was the PSU, which might work just fine one day, then not work the next day.

23 hours ago, jason74 said:

It could be your RAM, try using just 1 stick at a time and see if your PC posts. I had one of my RAM sticks fail without warning and as a result my PC would not power on.

It was one of the first things I tried because I know how RAM sticks can easily fail. Unfortunately it's not the Ram sticks. 

21 hours ago, stans said:

Could be a failed RAM stick.  In the failures to boot I have had, it was the PSU, which might work just fine one day, then not work the next day.

I don't think it is a failed RAM stick. I tried with one stick at a time. I think it is probably the PSU. I am going to see if it boots with a PSU I have from a previous build (Corsair HX650W). 

2 hours ago, BadKarmaPT said:

I don't think it is a failed RAM stick. I tried with one stick at a time. I think it is probably the PSU. I am going to see if it boots with a PSU I have from a previous build (Corsair HX650W). 

Depending upon your components, a 650 watt PSU may work or at least allow it to boot.  Some video cards draw a whole lot of power and will kill a PSU that cannot supply sufficient power.

On 12/24/2022 at 12:39 PM, stans said:

Depending upon your components, a 650 watt PSU may work or at least allow it to boot.  Some video cards draw a whole lot of power and will kill a PSU that cannot supply sufficient power.

I finally had time to test if it would work with my 650W PSU and it does. Not sure about how it will handle in the long term though. 

Now I have another issue. I have an M2 Nvme disk, an SSD and an HDD on my system and none of them are detected when I boot. I can get in Bios but when I exit, I go back to Bios because no boot device is detected. 

I'm pretty sure I connected everything correctly but I'll have to double check. I find it weird the M2 is not detected since it doesn't need any external connections. 

I hope this is not the case, but a PSU can take out the motherboard and/or components when it dies, that happened to me once.  What you might want to try is removing all drives except for the boot drive, see if you can get the BIOS to recognize the single drive.  If the BIOS still fails to find the boot drive, you may have either a motherboard problem or the drives got fried.

On 12/28/2022 at 12:57 PM, stans said:

I hope this is not the case, but a PSU can take out the motherboard and/or components when it dies, that happened to me once.  What you might want to try is removing all drives except for the boot drive, see if you can get the BIOS to recognize the single drive.  If the BIOS still fails to find the boot drive, you may have either a motherboard problem or the drives got fried.

I really hope that is not what happened here. I have to find the time to do some more tests. 

On 12/28/2022 at 12:57 PM, stans said:

I hope this is not the case, but a PSU can take out the motherboard and/or components when it dies, that happened to me once.  What you might want to try is removing all drives except for the boot drive, see if you can get the BIOS to recognize the single drive.  If the BIOS still fails to find the boot drive, you may have either a motherboard problem or the drives got fried.

Upon further testing I noticed my M2 Nvme disk is the only one detected. It is the drive where Windows 10 is installed but it won't boot into Windows. I was able to boot into recovery mode by using an USB drive. None of the recovery option work though... 

I tried the "Startup Repair" option first but after a few seconds I get a "Startup Repair couldn't repair your PC" message. 

Using the "Command Prompt" option I can see and explore my C:\ (boot) drive.

Both my D:\ and E:\ drives are not detected using this method and do not show in BIOS. 

Back to the drawing bord.

I would try reflashing the BIOS and if that doesn't allow drive recognition, I would return the Motherboard.

Yep, try to reflash the BIOS and hope that works.