Question Desktop computer not starting - Is Motherboard toast?

[NewDiyer]

Motherboard - Intel DB85FL
CPU - Intel i5 - 4440

My desktop computer was assembled in 2013. Suddenly stopped turning on.

I opened the ATX case side cover with everything intact to see what was happening. I couldn't find any sign of life - the PSU and CPU fans not running, no beeping sound.

I checked the CMOS battery. It showed 3.3 volts.

So, I decided to take everything out of the ATX case, and tried powering on with Motherboard, CPU, Ram, CMOS battery. Nothing happened, other than the green light [STDBY] coming on along with a continuous tick, tick sound until the PSU is switched off.

The PSU is working with paper-clip test. I checked the voltages with multimeter with PSU fan running. They were all giving the right output voltages.

With the 24 pin connected to the Motherboard and the top ends of the green wire and a black wire shorted with a paper clip, the PSU fan and the CPU fan rotate for about 5 seconds, then they stop, then again they start to rotate for 5 secs, and then stop. This happens until the power supply is switched off. What does this tell those who are experts / those who have come across this situation? Is it a Motherboard issue? There are no visible signs of damage on the Motherboard. The CPU pins look fine. I read somewhere that 90% of the time the CPUs are fine. I have tested by putting the RAM in different slots. No difference. What else should I check?

Thanks.

 

[DAPUNISHER]

You are connecting the 4 pin CPU power connector correct?

It is early, and I am not certain what you did with the 24 pin and the paper clip, but that does not read well. You should be connecting the 24 and the 4 pin CPU cables and short the power switch pins on the board, with a screw driver tip.

 

[NewDiyer]

Thank you Dapunisher. Following your advice I just had the CMOS battery one 4 GB RAM in place and connected PSU to the motherboard and the CPU fan to the 4 pins in a straight line [it says there CPU fan]. Turned on the PSU and shorted the power pins (2 red ones on the front panel). It gave the same tick tick tick sound continuously with the green light (STDBY) coming on. Please let me know what could be wrong, or if the motherboard is likely to be faulty.

I don't know whether this is relevant: I noticed 3 pins in the Bios security provided with a jumper. Jumper on pins 1 and 2 was given as normal; on 2 and 3 as security; and no jumper as Reset. I tried all three, and the result was the same as above - continuous tick tick sound and green light on.

Thanks for your assistance.

 

[Shmee]

Sounds kinda like the motherboard, though the PSU could be the culprit, just because it powers on and reads correct voltages, it could still be problematic at powering your computer. If you have a spare PSU, I would try with that. As Dapunisher mentioned, make sure both 24 pin on the motherboard and the CPU power are connected to PSU when testing.

 

[VirtualLarry]

You should be connecting the 24 and the 4 pin CPU cables

Following your advice I just had the CMOS battery one 4 GB RAM in place and connected PSU to the motherboard and the CPU fan to the 4 pins in a straight line [it says there CPU fan].

Err,NO. "4-pin CPU cable", means, the 2x2-pin ATX12V 4-pin 12V power cable coming from the PSU to the small square port on the mobo, to power the CPU properly. Then short the power-on front-panel pins with a screwdriver.

Edit: I would definitely try another PSU, if you can source one. I would say "90%" (well, maybe a little bit on the high side) of the time, if a PC "suddenly dies", it is because the PSU has given out. (Ok, maybe 80% of the time.) It can be the mobo too (maybe 10-15% of the time), and ... the other possibilities need more work.

Oh, and if you haven't done it yet, re-seat and blow off the RAM contacts with a can'o'air, or maybe some DeOxIt spray / contact cleaner.

 

[NewDiyer]

Err,NO. "4-pin CPU cable", means, the 2x2-pin ATX12V 4-pin 12V power cable coming from the PSU to the small square port on the mobo, to power the CPU properly. Then short the power-on front-panel pins with a screwdriver.

Edit: I would definitely try another PSU, if you can source one. I would say "90%" (well, maybe a little bit on the high side) of the time, if a PC "suddenly dies", it is because the PSU has given out. (Ok, maybe 80% of the time.) It can be the mobo too (maybe 10-15% of the time), and ... the other possibilities need more work.

Oh, and if you haven't done it yet, re-seat and blow off the RAM contacts with a can'o'air, or maybe some DeOxIt spray / contact cleaner.

 

[NewDiyer]

Thank you for pointing out that the 4 pin in this case is 2 x2 ATX. I just checked that again. Only the tick tick sound came. Can you comment on the point made to me that the tick tick sound in a bare bones connection on the motherboard means that the dead PC can't even make a beeping sound. That would perhaps suggest beyond a doubt that the motherboard is dead.

However, as a pretty much last step I would ask friends for a power supply and try it out as per the Editor's suggestion.

Thanks to both of you.