PC does not boot for unknown reason!!! HELP!

[AssemblerX86]

Hi,

So I have turned my PC off and went to sleep like I do everyday, but the next day, I push the power button, I get a BIOS message that all settings were reset to default, and then Windows gave BSOD while booting, this ONLY happened first time. Then when I restarted it, the CPU fan starts and the lights turn on, but there is no POST, the monitor stays black, the keyboard and mouse do not turn on, and it stays like this forever. Then this kept on happening each time when I turn the PC on. Speaker does not beep.

My specs:
- Motherboard: MSI 970A-G46
- CPU: AMD FX 6300 (No OC, HyperEVO 212 cooler)
- RAM: 4GB Kingston DDR3
- GPU: AMD Radeon HD 7750 (No OC)
- PSU: Huntkey GreenPower 550W (Had it for almost 4 years)

What I have tried:
1- Reset CMOS (Using Jumper and Battery Removal).
2- Swap RAM slots.
3- Getting CPU out and then placing it in again.
4- Trying another GPU (Nvidia Geforce 8400GS)
5- Disassemble everything and assembling them back again. (PSU cables, mouse, keyboard, etc...)
6- Discharging PSU capacitors using 30-second power button holding.
7- Using vacuum to clean the components.
8- CMOS Battery gives full 3V when testing it using a multimeter.

Maybe two times while desperately powering off and on, it turned on, but I got a message from the BIOS that all settings were reset to default, Windows gave a BSOD and then halted, the second time this happened, Linux worked flawlessly. In both times, turning the PC off wont make it turn on again.

I am desperate, if anyone solves this, I wont hesitate to select it as best answer as soon as possible.

 

[crystal_tech]

might need to plug the screen into the onboard video to get to bios and reconfigure it to use pcix card. also if your getting bsod it might be missing a ahci driver or ahci is turned off in the bios as well.

 

[AssemblerX86]

might need to plug the screen into the onboard video to get to bios and reconfigure it to use pcix card. also if your getting bsod it might be missing a ahci driver or ahci is turned off in the bios as well.

But neither keyboard LED nor mouse turn on, which means its not a GPU problem.

 

[Onus]

That it is resetting everything to defaults suggests it is not able to remember its settings. How old is the motherboard? While a multimeter may show 3.0V from the battery, it may still be weak.

 

[AssemblerX86]

That it is resetting everything to defaults suggests it is not able to remember its settings. How old is the motherboard? While a multimeter may show 3.0V from the battery, it may still be weak.

2 and a half years old or maybe a bit older.

 

[Onus]

Well, a new CMOS battery (a CR2032) cost around $3-$4, so I'd get one.

 

[AssemblerX86]

Well, a new CMOS battery (a CR2032) cost around $3-$4, so I'd get one.

Tried another battery from a different device, didn't work.

 

[Shaun o]

Without any doubt at all the cause is your four year old not very well branded power supply unit has gone to circuit heaven.

Give it a pat!, it did well to last four years of service.

Try a new power supply, or one from another system with enough or equal watt output.
Or borrow a friends so you can test it connected to your system.
If it works as it should.

Bin the four year old PSU, buy a new one.

 

[AssemblerX86]

Without any doubt at all the cause is your four year old not very well branded power supply unit has gone to circuit heaven.

Give it a pat!, it did well to last four years of service.

Try a new power supply, or one from another system with enough or equal watt output.
Or borrow a friends so you can test it connected to your system.

I have tried this PSU on an office PC and it worked, though the office PC is low-specs. And why would the BIOS settings reset if it was the PSU?

 

[Shaun o]

Exactly. that`s why i said use a power supply in your system with a equal watt output or more.
No point in trying the old psu on a system that requires less power from the old PSU.
It proves nothing, if the PSU is suffering from a lack of wattage output as the cause to why a system is not working that requires more power.

PSU degrade in output and efficiency the older they get gradual wear and tear.
And at four years old I dare say it is the case with the Green power 550W psu you have.

Think about it.
It works fine on a system with a lower power consumption.
But not yours that requires more power.
What have you got to loose by testing the system with a borrowed power supply to confirm it ?

 

[Onus]

The PSU would have been my next suggestion too. If your motherboard has non-solid electrolytic capacitors, go over it and see if any are bulging or leaking. This could have easily happened inside your PSU as well.

 

[AssemblerX86]

The PSU would have been my next suggestion too. If your motherboard has non-solid electrolytic capacitors, go over it and see if any are bulging or leaking. This could have easily happened inside your PSU as well.

MOBO has solid capacitors: https://www.msi.com/Motherboard/970A-G46.html#hero-overview

I have no one I can borrow his PSU, so I will be buying one soon.

 

[Onus]

Oops, misclicked. Well, hopefully that will fix it. If not, it may be something else with the motherboard; that would be unfortunate.

 

[AssemblerX86]

Without any doubt at all the cause is your four year old not very well branded power supply unit has gone to circuit heaven.

Give it a pat!, it did well to last four years of service.

Try a new power supply, or one from another system with enough or equal watt output.
Or borrow a friends so you can test it connected to your system.
If it works as it should.

Bin the four year old PSU, buy a new one.

I have spent 100$ on a new 650W PSU (ZALMAN ZM650 as recommended by a few people I have asked in this forum)... guess what? It's still not working!!!! AS IF I HAVE SO MUCH MONEY! What a disappointment