Computer starts up and immediately shuts off.

Looking for some advice on next steps on my machine that "died" last night.

Essentially while playing Warhammer Online last night there was a brownout at my house, followed by a quick outage, quick surge, brownout, and then no power for 10 minutes.

After about a half hour I went to turn everything back on, and my first machine (older one) turned on fine, no issues.

My main machine however...

Fans started spinning, one fan sounded particularly loud and then power dropped out. No BIOS Beeps, no video, nada. Even better, it did this in a loop until I disconnected power from the back.

So I proceeded to open it up, blow out the dust and start fiddling. Reseated all the PSU connections. Same deal.
The strangely loud fan was coming off the Vid card (an 8800 GTS). It was not a "bad sound" so much as it seemed the fan was going either way too fast or not fast enough.

At this point, Im thinking power supply got hammered, isnt supplying enough juice. Well, no problem! My older machine has an identical 650W Antec PSU. So I go through the hassle of ripping it out, flopping it.

Same issue.

I disconnect everything at this point, including ram, and plug in the mobo. Hit the power, I hear....clicking. By the power/reset switch. No BIOS beeps though. Add in RAM, goes back to same infinite power up / power down loop. I go through several thousand iterations of connecting different pieces in different order...

At this point I neatly put everything back in the cage and button it up since its 1am and I want to throw it through a wall.

My thought process:

1) First thought it was PSU, but working one had same issue. Even tried different surge protectors, etc thinking maybe that got fried.
2) Then thought issue was Graphics Card. Lack of BIOS beeps seems to rule this out though. I mean, THAT might still be fried too, but my old machine isnt PCIE so I have no way of telling
3) RAM? - Tried both separately, together, flopped arrangement. I doubt this though since even without RAM in the mobo wouldnt stay powered up.

That leaves me with the following thoughts:

4) Something is causing a short on the mobo somewhere (and how this would randomly correspond with the power spikes I have no clue)
-Next step is tonight take everything out and start from scratch to test this out.

5) Mobo is a piece of slag: Ok, so this is the most probable option in my eyes. I just wish I could get the thing to stay powered on and beep at me.

6) CPU: This is my least favorite option as I cant come up with a way to reliably test it.

Im posting to gather any other thoughts, suggestions, etc. I know plenty of us have had a machine sputter and die before and managed to resurrect them, so Im looking for ideas.

Tonight I am planning on:
1) Taking the mobo out of the case and going down to the bare essentials
2) Jumping the power switch to see if thats fluky
3) Clearing the CMOS and trying again with bare essentials.

Oh and machine and all peripherals are plugged into an APC surge protector.

Machine specs...

-COOLER MASTER Centurion 5 CAC-T05-UW Black Aluminum Bezel , SECC Chassis ATX Mid Tower Computer Case
-COOLER MASTER SAF-S84-E1 80mm Case Fan
-EVGA 640-P2-N821-AR GeForce 8800 GTS 640MB 320-bit GDDR3 PCI Express x16 HDCP Ready SLI Supported Video Card
-GIGABYTE GA-P35-DQ6 LGA 775 Intel P35 ATX Intel Motherboard
-Antec True Power Trio TP3-650 650W ATX12V SLI Certified CrossFire Ready Active PFC Power Supply with Three 12V Rails
-Intel Core 2 Duo E6850 Conroe 3.0GHz LGA 775 65W Dual-Core Processor Model BX80557E6850
-Seagate Barracuda 7200.10 ST3500630AS 500GB 7200 RPM SATA 3.0Gb/s Hard Drive
-CORSAIR Dominator 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 1066 (PC2 8500) Dual Channel Kit Desktop Memory Model TWIN2X2048-8500C5D
-LG 18X DVD±R DVD Burner with LightScribe Black IDE Model GSA-H42LK BK
Purchased August 2007

So if anyone has any other thoughts and advice that would be great. I already have a replacement MoBo on the way as right now I see that as my likely culprit but I can always return if somehow this Lazarus rises.

Thanks in advance...

 

While you have it apart, check to see if any of the capacitors on the motherboard, especially the ones by the power supply got toasted. If they look like they are about to explode, or have started seeping, thats your issue.

 

None of my tests last night got any better results. So I picked up a new MoBo to test that out.

Transferred CPU over to new Mobo with one stick on known good ram and same thing is happening.

Just to make sure, I tested out this PSU in another machine again and it powered it without issue.

At this point I am thinking maybe the CPU itself?

 

on every power supply there is a red switch that makes the incoming voltage from the wall compatible to run it (for instance one setting on there is set to 240v for europe and 120v for america) depending on where you live

just try it if it doesn't work then set it back to where it was before
this is usually the case for this issue but thats my theory hope i was helpful

 

Good suggestion and I am familiar with that switch, yet oddly on both of my antec 650W PSUs that switch does not exist.

I ran out and bought a new PSU too just to make extra sure that both of mine werent falling below spec for my machine.

After some more playing around, I can supply constant power unless the 12v power connector for the CPU is plugged in. So Ive switched out everything except the actual CPU. I wouldnt normally think its the CPU since amongst my friends and I we've only ever seen one blow out.

Its the only untested thing, so I guess its up next...

 

I'm having a very similar situation with my machine right now, and it's driving me absolutely insane.. I've never seen any probem like this in over 15 years of working on computers.. I've tried a new motherboard, new PSU, bare-bones setup, BIOS clear, everything that usually fixes the problem doesn't do anything. I am completely stumped. Did you manage to get your machine working FMoosey?

I've got a Gigabyte P35C-DS3R motherboard that won't POST and gets no beeps at all, just keeps powering up and down in a loop cycle for a bit and then the CPU fan spins up to high and stays there, still w/ no beeps. So I swapped in a brand new Gigabyte GA-EP45-UD3R, and it does the same power on/off cycle, and once in a while it'll give constant short beeps, which according to the pretty-much-useless manual indicates a "Power problem" with no further descriptions. I've tried a new power supply and that didn't help at all. The gigabyte website also has no real support that's useful. I've tried booting w/ just the CPU and 1 stick of known good RAM, same thing..throw in the GPU, same thing.. I've tried everything in the case, and out of the case, jumped the power switch, etc.. there's no shorts anywhere, no blown capacitors. Can anyone offer any further insight? I'm A+ certified, and have asked many other techs with similar credentials and we're all baffled. What else can I try?

 

I thought it relevant to post here because our problem is exactly the same, and there was not really a resolution to this thread. I was just wondering if the problem had been resolved.

 

Sorry to hear you are going through the same hassle. Its incredibly frustrating. I am waiting on a new CPU, its the only thing I hadnt switched out, so once that comes in I will let you know if that resolved.

Hope you come up with something soon yourself, its just an annoying situation.

 

One more day of trying out the same old solutions. Really the only thing I can think of that's left to test is the processor. I'm in the same thought process as you FMoosey, in that I've never seen a processor die.. not ever. So that's always the last thing I suspect. But, with the POST beeps every once in a while, it seems like that could be a likely problem, seeing as the CPU is one of the first things tested by POST, and if there's a problem with the CPU it woulld likely cause a problem with the power flow. I just find it hard to believe that a CPU would die in less than 2 years, never having gone above 34c.. Keep in touch and let's try to figure this out. Everyone I've talked to about this is curious to see what fixes the problem.

 

Well, I've now put in a new CPU and still no luck getting a POST on either motherboard... I sure am stuck on what the heck could be causing this. Did you get yours working FMoosey?

 

Hey FMoosey, did getting a new CPU fix your problem?

(I have the same issue that you mentioned, right down to disconnecting the 12v to the CPU causes the PC to stay powered on.)

Also, in doing searches, I've found several threads related to 'power supply shuts down' that show an Intel Core 2 Duo XXXX processor. Not sure if that says anything about the processor going bad, but it could be an issue, I suppose.

For reference mine is an Intel Core 2 Duo E8400... I'm having my system RMA'd which will take some time to determine the problem. (HP Blackbird 002)

Just thinking that others could benefit from a solution to this problem-- thanks!

 

So I just recently got confirmation that my motherboard had caused the problem. It has been replaced to fix this issue.

If there was anything else replaced I'll let you know.