PC powers on for one second then powers off

[D!ABOL!C]

Hello Friends!

 

I'm having an issue with a spare PC I have and wanted to pick your brains. About a week and a half ago, I was using my spare PC and it was running great. I usually leave it off, only use it for testing etc. A couple days ago, I went to power it on and the fans spin up and the lights come on for about a second, then it cuts off. From that point, I cannot turn it on even switching off the switch. If I plug it in to another power outlet, it does the same thing, powers on briefly, then off. Nothing had changed between the times I used it last and when the issue started.

 

I brought my computer in to work on at the office and completely removed everything. I removed the power supply and removed the motherboard from the case. I reapplied thermal grease and got everything plugged in. Unfortunately, it does the same thing. I'm guessing it is the power supply, but wanted to get a few other expert opinions before buying a new power supply. I'll list the important components below. Any thoughts? Thank you kindly!

 

PC in questions:

 

Motherboard: Gigabyte GA-P35-DS3L

CPU: Intel E6750 C2D

Power Supply: Silencer 600W

[PsYcHoKiLLa]

Have you tried removing individual memory sticks and trying again? Personally I think it might be the CPU if the system is getting power and not going any further. Check the CPU power block (4 pin/8pin) is correctly inserted?

It's not giving any audio warnings or code on the mobo for an error code?

[D!ABOL!C]

I will give that a shot and see.

 

I have the 24Pin power plugged in as well as the 4Pin for the CPU.

 

In regards to the CPU it self, you could be right. When I initially just unplugged the power cables and plugged them back in, I bumped the HSF. I forgot to mention I have a giant Zalman9700 LED HSF on the CPU. When I bumped the HSF, it did slide a little on top of the CPU. That is why I reapplied the thermal grease etc.

 

I will give the memory a shot first.

[PsYcHoKiLLa]

I would be more inclined to check the 4pin block for the CPU is properly clicked in, if it's not then the mobo might not be "seeing" the CPU as present.

[D!ABOL!C]

It's definitely clicked in. Due to how large this Zalman HSF is and how little wiggle room I have inside the case, I made sure I plugged the 4Pin into the motherboard before securing it to the case.

[DevTech]

2 minutes ago, D!ABOL!C said:

It's definitely clicked in. Due to how large this Zalman HSF is and how little wiggle room I have inside the case, I made sure I plugged the 4Pin into the motherboard before securing it to the case.

Make sure there is a little speaker plugged into the motherboard pins near the power/reset jumper pins

[D!ABOL!C]

1 minute ago, DevTech said:

Make sure there is a little speaker plugged into the motherboard pins near the power/reset jumper pins

I don't see a speaker anywhere on the motherboard.

[DevTech]

Given your description, the one thing that wears out by just standing there is the motherboard CMOS battery

 

With or without that issue, the BIOS settings sometimes just corrupt over time so do the "clear CMOS" thing

 

Just now, D!ABOL!C said:

I don't see a speaker anywhere on the motherboard.

so plug one in so you hear the BEEP CODE

[D!ABOL!C]

3 minutes ago, DevTech said:

Given your description, the one thing that wears out by just standing there is the motherboard CMOS battery

 

With or without that issue, the BIOS settings sometimes just corrupt over time so do the "clear CMOS" thing

 

so plug one in so you hear the BEEP CODE

I just popped the CMOS, i'll plug it back in and give it a shot.

 

Unfortunately, I do not have a speaker laying around.

[DevTech]

Oh darn, the other thing that deteriorates is motherboard caps...

 

examine all motherboard caps for absolute flatness on top, not even the tiniest bulge, and of course any hint of that nasty brown leakage..

 

1 minute ago, D!ABOL!C said:

I just popped the CMOS, i'll plug it back in and give it a shot.

 

Unfortunately, I do not have a speaker laying around.

steal one from another computer or jumper in any audio speaker!

 

every computer should have that tiny little beeper that would add a penny to the cost!

 

[DevTech]

You can also open the power supply and check the caps there as well... I see lots of that

[D!ABOL!C]

The PC doesn't stay on long enough to make POST. If I plug it in the fans spin up for 1/2 a second and then nothing. So it does look like power is getting to the motherboard, I guess.

 

The CMOS removal didn't work.

[DevTech]

5 minutes ago, D!ABOL!C said:

I just popped the CMOS, i'll plug it back in and give it a shot.

 

Unfortunately, I do not have a speaker laying around.

with residual capacitance etc, you can't just remove the battery unless you let it sit for 10 minutes. That's why there is a jumper to short it out right next to the battery somewhere... only need to contact it 1/2 a second

 

Core 2 CPUs are super reliable and keep on ticking forever so it is power supply or mobo

[PsYcHoKiLLa]

Not being funny but the first time you tried turning it on and it didn't work, did you smell electrical burning or hear a pop?

[D!ABOL!C]

1 minute ago, PsYcHoKiLLa said:

Not being funny but the first time you tried turning it on and it didn't work, did you smell electrical burning or hear a pop?

I notice any smells. When I turned it on the first time it wouldn't, I was wondering why it wasn't staying on.

[DevTech]

4 minutes ago, D!ABOL!C said:

The PC doesn't stay on long enough to make POST. If I plug it in the fans spin up for 1/2 a second and then nothing. So it does look like power is getting to the motherboard, I guess.

 

The CMOS removal didn't work.

There is a tiny computer in every mobo that does a check before letting the vast current from the on-board regulators through to the CPU.

 

The fans spin up, it doesn't like something and it shuts off the PSU.

 

[DevTech]

Make sure the mobo is sitting on a piece of cardboard or wood

 

Then examine top and bottom carefully for scrap metal  or other foreign object. I have even heard of a spider leg causing a minor short.

 

[DevTech]

So far without more data and without beep codes, I'd go for bad caps in mobo or power supply causing voltage to fluctuate enough to trigger shutdown.

 

Sometimes they go bad with no visible sign.

 

[D!ABOL!C]

I'll try pulling the motherboard out of the case on a piece of card board and see if I can get it to boot. If it doesn't power on at that point, i'm just going to drop it off at my local computer place. I don't have any other spare parts to sub in for further testing if it is indeed the motherboard or CPU. Thank you for the ideas!

[sc302 Veteran]

If you have blown capacitors, it may not stay on for long.  

 

If you have a bad psu it will not stay on for long (though it may power on...I had one that did the same).

 

Those are the two main issues that I can see.  Could be other issues, but generally if it were a bad processor or bad memory it wouldn't immediately power off...unless the motherboard couldn't detect the processor fan...

[DevTech]

The Industry's Leading All-Solid Capacitor motherboard Design

 

To ensure a longer operation life time for systems in daily operation and boost system stability under extreme conditions, this platform adopts cutting-edge Conductive Polymer Aluminum Solid Capacitors from the world's leading vendors. With these high-qualitycomponents , users can take advantage of better electronic conductivity and excellent heat resistance for enhanced system durability.

 

https://www.gigabyte.com/Motherboard/GA-P35-DS3L-rev-20#ov

 

These caps unlikely to go bad. If they do there would be no visible sign.

 

[Mindovermaster Moderator]

Look at the board for any bulging capacitors.

 

I ALWAYS have this around. It's a life saver, believe me.

 

https://www.amazon.com/HighSpeed-PC-ATX-Control-Kit/dp/B015JLMUI4/ref=cm_cr_arp_d_product_top?ie=UTF8

[sc302 Veteran]

1 minute ago, DevTech said:

The Industry's Leading All-Solid Capacitor motherboard Design

 

To ensure a longer operation life time for systems in daily operation and boost system stability under extreme conditions, this platform adopts cutting-edge Conductive Polymer Aluminum Solid Capacitors from the world's leading vendors. With these high-qualitycomponents , users can take advantage of better electronic conductivity and excellent heat resistance for enhanced system durability.

 

https://www.gigabyte.com/Motherboard/GA-P35-DS3L-rev-20#ov

 

These caps unlikely to go bad. If they do there would be no visible sign.

 

not outside the relm of possiblity...neither is a midget killer clown.... but you don't see many of them either.

[DevTech]

1 minute ago, D!ABOL!C said:

I'll try pulling the motherboard out of the case on a piece of card board and see if I can get it to boot. If it doesn't power on at that point, i'm just going to drop it off at my local computer place. I don't have any other spare parts to sub in for further testing if it is indeed the motherboard or CPU. Thank you for the ideas!

Given the high quality caps on that mobo, unscrew the four tiny screws on the power supply and pop it open enough to examine the caps. For sure it won't have high quality ones like the mobo!

 

If you see a smoking gun there, temp borrow a PSU from another computer...

 

[D!ABOL!C]

I did scan the motherboard, didn't see any bulging or brown capacitors. I am going to take the motherboard out of the case in a few minutes to get a thorough look though.