Power problems with new build

[catallyst74]

So I posted about this problem the other day, thought I'd fixed it, and apparently not...

When I turn on my new build, it will run for about `15 seconds, then will shut down for a few seconds, then start up again. It does this over and over. A little tester came with the PSU so I tested it and it stays on fine during the test. All I have connected right now is the PSU, motherboard and the cpu cooler and the same thing is happening...so if the PSU tested ok, am I to assume that the motherboard is bad?

CPU: Intel Pentium G3258 3.2GHz Dual-Core Processor
CPU Cooler: Arctic Cooling Freezer 7 Pro Rev.2 45.0 CFM Fluid Dynamic Bearing CPU Cooler
Motherboard: Gigabyte GA-B85M-DS3H Micro ATX LGA1150 Motherboard
Case: Corsair SPEC-03 Orange ATX Mid Tower Case ($39.99 @ Newegg)
Power Supply: EVGA 600B 600W 80+ Bronze Certified ATX Power Supply ($19.99 @ NCIX US)

[Remilia]

Potentially dumb question, but is the CPU connector connected?

[catallyst74]

Potentially dumb question, but is the CPU connector connected?

Yes it is.

I notice that on newegg there's quite a few reviews saying their boards came DOA so my suspicions are rising here..

[Deleted]

You did remember the risers between motherboard and the case?

[wregelmann]

Could be overheating, but that is very quick if it's 15 seconds from a cold boot. The CPU cooler is working?

[catallyst74]

Could be overheating, but that is very quick if it's 15 seconds from a cold boot. The CPU cooler is working?

The CPU fan runs when i turn the power on.

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You did remember the risers between motherboard and the case?

I'm going to sound like an incredible noob here, but what do you mean by risers?

[potis]

He means the copper screws that you place into the case so the motherboard will be held up and screwed into those so it wont be touching the case and pretty much short circuit, aka "risers".

[catallyst74]

He means the copper screws that you place into the case so the motherboard will be held up and screwed into those so it wont be touching the case, aka "risers".

Oh ok, I thought that's what you meant...I think so. Maybe I missed some? I should go back and check on that.

[Kagthul]

The behaviour youre describing is exactly what happens when you attempt to power on a computer that does not have the 4-pin power connector for the CPU plugged into the motherboard. Not the big 24(?) pin block, but an entirely separate little 4-pin square block connector, usually nearer to the CPU.

Check and make sure its seated firmly and is in fact plugged in. Because, like i said.. that's *exactly* what will happen if it isnt.

Also make sure (if its got one) that the PSU is switched the the correct amperage. A lot of modern PSUs dont have a switch (they auto detect) but many still do.

[catallyst74]

The behaviour youre describing is exactly what happens when you attempt to power on a computer that does not have the 4-pin power connector for the CPU plugged into the motherboard. Not the big 24(?) pin block, but an entirely separate little 4-pin square block connector, usually nearer to the CPU.

Check and make sure its seated firmly and is in fact plugged in. Because, like i said.. that's *exactly* what will happen if it isnt.

Also make sure (if its got one) that the PSU is switched the the correct amperage. A lot of modern PSUs dont have a switch (they auto detect) but many still do.

Here's the manual for my motherboard:

http://download.gigabyte.us/FileList...s3h_v2.x_e.pdf

My power is the 2x4 pin in the upper left corner, correct? If so I did have that plugged in.

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There is no switch on my PSU.

[Deleted]

This often happens when people forget the 8-pin stick to the motherboard, or doesn't put the RAM in the right way. :-)

[catallyst74]

I don't know, I'm at a loss. Far as I can see everything is connected where it should be. I keep feeling like I'm missing something but I've already checked everything you guys have mentioned.

[Kagthul]

Both the ATX (24 pin, upper right), and CPU power (2x4pin, upper left) need to be plugged in. Sometimes the 24 pin connector will actually be 20+4 (my current PSU, its 20+4, my last one, it was a solid 24 pin block), make sure its all plugged in. Dont be afraid to unplug and reseat all the power cables just to make sure. If the PSU is modular, make sure they are all firmly seated on that end, as well.

Another thing to make sure of is that you didnt put a 6+2 into the CPU power - those are for a GPU. I dont -think- a 6+2 would fit (corners are generally rounded differently so they wouldnt fit).... but check anyway. Cant hurt.

If all the power is plugged in, and you're not getting any joy... its likely a bad MoBo... but could also be a bunk PSU, if one of the power cables is bad (say one of the 4x2s for CPU power) that could cause it (as it wouldnt be delivering power). Do you have a spare PSU you can test with, from an old rig? You wouldnt even have to install it into th machine, just plug the cables in and power it on to see if it posts. That would at least tell you its not the PSU and is either the MoBo or (far less likely) the CPU itself.

Does it post anything to your screen at all? Even the MoBo manufacturer flash screen or a BIOS post screen, or it just trying to turn on, and then failing immediately before it shows anything?

And definitely check for the risers. If the board is grounded... yikes. Could be very bad and may have torched the MoBo. (In my experience, though, its probably not this - if you HAD shorted the board across the case, it would have failed... if not spectacularly, definitely visibly arcing and sparking and making noises it shouldnt). So it probbaly isn't this, but you can never be too careful when checking things out.

Also make sure the RAM, GPU, et al, are seated firmly too.

[catallyst74]

Both the ATX (24 pin, upper right), and CPU power (2x4pin, upper left) need to be plugged in. Sometimes the 24 pin connector will actually be 20+4 (my current PSU, its 20+4, my last one, it was a solid 24 pin block), make sure its all plugged in. Dont be afraid to unplug and reseat all the power cables just to make sure. If the PSU is modular, make sure they are all firmly seated on that end, as well.

Reset the power cables plenty of times, everything seems to be in tight. My 24 pin is a 20+4 and I think I've got it in tight (the 4 pin part was a bit of a pain)

Another thing to make sure of is that you didnt put a 6+2 into the CPU power - those are for a GPU. I dont -think- a 6+2 would fit (corners are generally rounded differently so they wouldnt fit).... but check anyway. Cant hurt.

No, I didn't do that, I've got 2 4-pin plugs.

If all the power is plugged in, and you're not getting any joy... its likely a bad MoBo... but could also be a bunk PSU, if one of the power cables is bad (say one of the 4x2s for CPU power) that could cause it (as it wouldnt be delivering power). Do you have a spare PSU you can test with, from an old rig? You wouldnt even have to install it into th machine, just plug the cables in and power it on to see if it posts. That would at least tell you its not the PSU and is either the MoBo or (far less likely) the CPU itself.

I unfortunately don't have a spare psu. I wish I did because I'd rather know which part is faulty so I can send it back and get a good one. I'm kind of leaning towards it being a bad wire in the PSU.

Does it post anything to your screen at all? Even the MoBo manufacturer flash screen or a BIOS post screen, or it just trying to turn on, and then failing immediately before it shows anything?

Fails before it shows anything.

[Hellsgrundle]

Silly question, did you apply thermal paste (or was it already applied) to the cooler before attaching to the cpu? Is the cooler firmly installed over the cpu? I highly doubt it would fail so quickly if this were the case, but it's worth covering all bases.